With an in-line booster, the problem changes. If you re pumping for elevation between pressure zones, you can still use that reservoir assumption once you decide on the nominal HGL in each pressure zone. However, if you re pumping primarily to overcome head loss over a long distance, the pump selection and pipe sizing cannot be separated. In that case you just need to do a lot of trial and error solutions. This is where scenario manager is very powerful. You can try different size transmission mains and see what pumps you'll need. There will be a tradeoff in that larger pipes will require less pumping energy. WaterGEMS' energy costing tools will help you determine that part of the design. The process would be pick a pump(s), use Darwin to size pipes, run energy costing, determine the life cycle costs. Then pick another pump and repeat. Look at the tradeoffs. Once you get a good solution, make EPS runs to look at operation during a range of conditions.
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Forum Post: RE: Pump and Darwin Designer
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Wiki Page: Creating a DGN file from a hydraulic model, with annotations hidden
Product(s): WaterCAD, WaterGEMS, HAMMER, StormCAD, SewerCAD, SewerGEMS, CivilStorm, PondPack Version(s): V8i, CONNECT Edition Area: Output and Reporting Problem How can I create a DGN from a hydraulic model file, with color coding and/or annotation not showing? For example to reference water model piping with other linework in regular MicroStation (not integrated with the Haestad product.) Solution In some cases you may have a need to reference in a hydraulic model file in MicroStation. For example you may have a sewer and water system and would like to see both at the same time, or want to have a final figure to print, with all types of networks. There are a few different possible ways to accomplish this. Option 1 Use the "Element Levels" tool in the MicroStation integrated version of the Haestad product (such as "WaterGEMS for MicroStation") to assign all annotations to a separate level, then turn off that level before saving/exporting the DGN. Note that this needs to have been configured before the model was attached to the DGN or before the annotations were created. See more: Assign elements and annotations to specific levels when a project is attached to a DGN in MicroStation So, if this was not already done, you could configure the "Element Levels" to put all annotations on a separate level, then delete and recreate the annotations, then hide the respective level in the level display manager. Option 2 In the MicroStation integrated version of the Haestad product, uncheck the annotations/labels in Element Symbology, choose "File" from the Haestad product's menu, select "Save Symbology to Drawing", save the file, then reference it as needed. Option 3 Open the hydraulic model in the Standalone version of the Haestad product, turn off (uncheck) the annotations in element symbology, export to DXF via File > Export > DXF (Which also has options as to how to export the layers), then add as a reference in MicroStation. See Also Assign elements and annotations to specific levels when a project is attached to a DGN in MicroStation How to detach / disassociate a model file from the Microstation DGN file
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Wiki Page: "... Stopped Working" error when opening product
Applies To Product(s): WaterGEMS, WAterCAD, StormCAD, SewerGEMS, SewerCAD, CivilStorm, FlowMaster, PondPack Version(s): 08.11.xx.xx Area: Installation Original Author: Jesse Dringoli, Bentley Technical Support Group Problem When opening the standalone version of WaterGEMS or one of the other Hydraulics and Hydrology products or when trying to open or create a hydraulic model, a window appears with an error like "Bentley WaterGEMS has stopped working" and the program does not open. Solution This is a generic crash that can occur in a number of different situations, mostly related to operating system components or other supporting prerequisites. Here are some cases that have come up before: Case 1 The "Stopped working" error can occur starting in version 08.11.06.113 (WaterCAD/WaterGEMS/HAMMER) / 08.11.05.113 (SewerGEMS/CivilStorm/StormCAD/SewerCAD) with some versions of the CONNECTION client. First, make sure you have the most recent version of the CONNECTION Client installed. This can be found in the Windows system tray - you can typically right click and choose to update. Also, try logging into the CONNECTION Client after updating. In some cases you may need to exit the CONNECTION Client and the Haestad product, reopen the CONNECTION Client (check the Windows start menu to find it), log in, then open the Haestad product. Also, if possible, try running the Haestad product as Administrator - right click on the shortcut and choose "Run as Administrator". Case 2 If using a 64-bit Operating System, try opening the 32-bit version of the program first, create a new model, then try opening the program normally (such as from the Desktop shortcut). For example the 32-bit version of WaterCAD is C:\Program Files (x86)\Bentley\WaterCAD\WaterCAD.exe Case 3 First, try compacting the database. To do this, close the model but leave the product open. Go to Tools > Database Utilities > Compact Database. Select the database file and choose the option to purge the model to save space. Once completed, open the model and see if the issue still occurs. This is an indication that the output files are too large or numerous. Try creating a new folder and moving just the starter file and the database file (.wtg and .wtg.sqlite for the water products, .stsw and .stsw.sqlite for the storm and sewer products) to the new folder. Once done, open the model from the new folder location. If that doesn't help, try importing the database into a new drawing. This is done by going to File > Import > (product name) database. Lastly, you can also try deleting the engineering library database. Go to c:\users\ \AppData\Roaming\Bentley\EngineeringLibraries and delete EngineeringLibraries.mdb and EngineeringLibraries.sqlite. Make sure the program is closed when you do this. When you open the program again, the files will get re-created. Note: Custom items in the engineering library will be lost if you do this. Case 4 Product: WaterGEMS 08.11.05.61 and SewerGEMS 08.11.04.54 64-bit version (32-bit version did not experience the problem) Operating System: Windows 8.1 Language: Spanish In this case, the Windows Event Viewer Application log contained a separate entry corresponding to the time of the crash, indicating an issue with "VC80". The issue was resolved by uninstalling the apparently conflicting or corrupted version of Microsoft Visual C++ 2005 Redistributable (x64) 8.0 from the Windows "Programs and Features" tool, then reinstalling the product, which reinstalls this component. Case 5 Product: WaterCAD 08.11.05.61 64-bit version Operating System: Windows 8.1 Language: English In this case, the Windows Event Viewer Application log contained a separate entry corresponding to the time of the crash, indicating an issue with "CLR20r3". Running a scan on the system resulted in the following: It appears the issue has to do with the .NET Framework component that is a part of the operating system. The user had a repair done on his operating system to resolve this issue. Case 6 Another option would be to run a Repair on the program through the Control Panel (Control Panel > Programs and Features). After doing this, right-click on the shortcut for the program and select Properties. In the Compatibility tab, place check mark for the item "Run this program as an administrator". Also click on "Change settings for all users" and make sure that "Run this program as an administrator" is set for there as well. Case 7 This involves reinstallation of the Microsoft .NET Framework prerequisite. 1) Uninstall the Haestad product (from Windows "Programs and Features"). Preferably, do a clean reinstallation (removing leftover components after uninstalling) 2) Uninstall all Microsoft .NET framework versions, which need to be uninstalled in descending order. This may require you to uninstall Windows Media Player. 3) Restart your computer 4) Perform a registry cleanup. (Perform this step if comfortable - if not, try proceeding to the next steps) This can be done with a number of registry cleanup utilities, such as "CCleaner". This may locate and repair missing entries related to .NET Framework. 5) Reinstall and check if the error no longer occurs. Reinstallation of .NET Frameworks may also require reinstallation of Windows Media Center. 6) If the problem still occurs, try checking for any new additional updates to the .NET framework that are available. You may also want to check for recent Windows Updates of ".NET security and quality rollup". Possible related links: 1 | 2 Case 8 Products: FlowMaster 08.11.01.03, PondPack 08.11.01.56 Note: This workaround will not apply to Bentley Hydraulics and Hydrology applications other than the ones listed above. Try opening the following managed starter file. For FlowMaster: C:\Program Files (x86)\Bentley\FlowMaster\FlowMaster.Starter.exe For PondPack: C:\Program Files (x86)\Bentley\PondPack8\Haestad.PondPack.Starter.exe Opening the application using this file should not have any adverse effects. If the program opens without the error, then do the following to create a desktop shortcut. Right-click on the file listed above, which corresponds to the application having the issue > Create Shortcut > Yes (to place it on your desktop). Right-click on the new desktop shortcut > Properties > Compatibility tab > Change settings for all users > Check "Run this program as an administrator" > Apply > OK > OK. What if none of these help? Generate a "dump" file and send it to technical support for investigation. To do this: 1. Start the Haestad product (such as WaterCAD) 2. Do not close the Application has stopped working window 3. Run Windows Task Manager (press Ctrl-Shift-Esc or right click in the bar at the bottom of the screen and select “Start Task Manager” ) 4. In Task Manager, go to the Processes tab and right-click on the crashed process 5. Select Create Dump File You can compress this into a zip file and upload it as an attachment to your forum post here or your service request here (log in to the CONNECTION Center then click the "New Service Request" link). If the file is too large, request an upload link from technical support.
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Wiki Page: How is flow balanced at junctions with the GVF Rational Solver (StormCAD)?
Applies To Product(s): Bentley SewerGEMS, Bentley CivilStorm, Bentley StormCAD Version(s): 08.11.XX.XX Original Author: Mark Pachlhofer, Bentley Technical Support Group Problem How is flow balanced at junctions with the GVF Rational Solver (StormCAD)? Solution Because of the use of rational method hydrology, flow discontinuities may be noticed. This is a condition where the sum of the inflows does not equal the sum of the outflows. The main reason for this is that the rational method is only concerned with peak flows and has a high dependence on duration (system time). As the system time changes, the intensity changes and has a direct effect on the rate of flow in the system. The most common cause of confusion with this discontinuity stems from rational loads that are tracked through a long piping system without any other loads entering the network. At the inlet of origin, the time of concentration may be relatively small, resulting in a high intensity and a large peak discharge. As the load travels through the pipes, the system time becomes larger, so the intensity lowers. This results in smaller discharge values, so the peak flow at the outlet may be significantly smaller than the peak flow at the original inlet. This may seem counter-intuitive at first, with questions like "Where did the rest of the flow go?" coming to mind. In reality, the rest of the flow was not lost, but an attempt to balance peak flows is not valid. Picture standing at the top of a hill with a bucket of water. If you empty the entire bucket into the gutter in one second, then the peak rate of discharge at the top of the hill is one bucket per second. Racing to the bottom of the hill, you can observe the flow and see that the peak flow is much less than one bucket per second. However, the flow lasts longer than one second. There was no water lost, but the peak was lower. StormCAD does not simply add flow at a junction node; rather, it takes into account the attenuation of peak flow as one moves downstream by keeping track of upstream catchment properties and decreasing the peak intensity according to the time of concentration and travel. The flow out of a catchment is: Where : Q = Flow C = Coefficient i = Intensity a = Area And the flow out of a junction is: Q (out) = Sum (C * i * a) + Sum (Q known) One would think therefore that flow in equals flow out. However, the intensity (i) used for determining the flow into the manhole will be higher than the intensity of the flow leaving the manhole. This intensity is calculated using the longest possible flow travel time in order to generate the most conservative value for peak flow. For example, say a catchment empties into a catch basin and has a Time of Concentration of 10 minutes. On the other hand the travel time of the piped flow getting to the catch basin is 12 minutes. The rational flow generated at the catch basin will be generated based on the intensity associated with the 12 minute duration. This way you are assured that the whole system is contributing to the flow and hence you are using the most conservative peak flow value at that point. If you do not wish to have this flow attenuation taken into account, you should specify Known or Additional flows at the catch basins. If this situation occurs in a Carrier Pipe (multiple pipes in series, with no catchments connected to nodes along the pipes), you can also use the "Ignore Travel Time in Carrier pipes? " Calculation option. This allows the modeler to eliminate the flow reductions that would otherwise occur as a result of the increased system time in these cases. For more on this including illustrations, see the section in the Help called "Carrier Pipes". There is also an option to correct for partial area effects. This makes the GVF-Rational solver adopt the largest system time from all the incoming flows that converge into a node. It can be set in the calculation options by changing the "Correct for Partial Area Effects?" property. See Also Flow Attenuation - Why does flow or velocity sometimes decrease when moving downstream? Why is the system time at one of my nodes much larger than the upstream nodes Tc or system time?
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Wiki Page: Is it possible to see different results between WaterGEMS and WaterCAD?
Product(s): WaterGEMS, WaterCAD Version(s): 10.00.xx.xx, 08.11.xx.xx Area: Modeling Original Author: Scott Kampa, Bentley Technical Support Problem Is it possible to see different results between WaterGEMS and WaterCAD? Problem ID#: 87849 Solution WaterGEMS and WaterCAD are the same program, with the only difference being available licensing features. That being the case, results should be the same. If they are not, please make sure that the same version of the program is installed, as well as the latest patch for each product. Note: if one program is installed on a 32-bit machine and one on a 64-bit machine, there may be small differences in results because of operating speed, but the difference would be minimal. See Also What is the difference between WaterGEMS and WaterCAD?
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Water Training: Water Distribution Design and Modeling Fundamentals
Register Here 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. After completing this course, you will be able to: - Apply the basic principles of water distribution modeling; - Gain essential knowledge for water system design, operation, and troubleshooting; - Apply WaterCAD/WaterGEMS models to solve common water distribution system problems; - Develop a deeper understanding of model creation and analysis using WaterCAD/WaterGEMS; - Increase productivity by using automated approaches to complete common modeling tasks.
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Water Training: Water Distribution Design and Modeling Fundamentals
Register Here 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. After completing this course, you will be able to: - Apply the basic principles of water distribution modeling; - Gain essential knowledge for water system design, operation, and troubleshooting; - Apply WaterCAD/WaterGEMS models to solve common water distribution system problems; - Develop a deeper understanding of model creation and analysis using WaterCAD/WaterGEMS; - Increase productivity by using automated approaches to complete common modeling tasks.
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Water Training: Water Distribution Design and Modeling Fundamentals
Register Here 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. After completing this course, you will be able to: - Apply the basic principles of water distribution modeling; - Gain essential knowledge for water system design, operation, and troubleshooting; - Apply WaterCAD/WaterGEMS models to solve common water distribution system problems; - Develop a deeper understanding of model creation and analysis using WaterCAD/WaterGEMS; - Increase productivity by using automated approaches to complete common modeling tasks.
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Storm Training: Stormwater System Design and Modeling (Advanced) using CivilStorm and SewerGEMS
Register Here In this course students will learn and apply software features to realistic drainage situations. Students will approach drainage design and analysis using an entirely new and cutting-edge modeling paradigm – unsteady flow routing through interdependent systems of inlets, storm sewers, channels, culverts, and ponds. Students will also unify drainage components into a single model that runs within the Windows or CAD environment. Students will learn to calculate runoff hydrographs, create hydraulic grade lines through pipes, channels, culverts, and ponds, and then animate those profiles over time. Students will compare results for various events and design alternatives, color-code system elements over time, locate potential flooding, import aerial photography, establish background layers, setup a pre-developed model, and then design a proposed drainage system. Skills Taught: - Design and simulate complex stormwater systems; - Model the dynamic interaction between all components of a stormwater system; - Design more effectively.
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Forum Post: PondPack as microstation utility VS PondPack as stand-alone program: Pros/Cons?
I work for an engineering consulting company and about annually I do stormwater analysis & design for landfills (40-400 acre facilities). The stormwater analysis & design generally includes sizing/design of conveyance diversion berms along landfill slopes, downslope pipes/flumes to base of landfill, open ditches around the base of the landfill, and culverts leading to detention/infiltration basins for 25-50-100 year design storm events. Over the last 10 years I have done the stormwater analysis in MS excel, but I am now entertaining moving the stormwater analysis into a product like PondPack for microstation. I am attempting to weigh the benefits of operating PondPack as a utility of microstation, vs PondPack as a stand-alone program, vs any other stand-alone stormwater program for that matter (XP, hydroCAD,etc). Specifically I am wondering if PondPack for microstation can perform stormwater calculations and/or update stormwater design features "on-the-fly" that stand-alone programs can't? For instance if slope or curve number or acreage change for a given design storm event, can/will PondPack for microstation update diversion berm, pipe/flume, ditch, culvert, and/or basin designs to accommodate the change in hydraulic condition? From my perspective this would add value to the workflow because it would eliminate iterations between the analysis workflow and design workflow. Namely; WORKFLOW A. generate stand-alone program output, hand it off to cad folks, and then cad folks update microstation files with revised design, VS, WORKFLOW B. microstation program output updates microstation design files on-the-fly. Thanks for your thoughts and education.
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Forum Post: RE: PondPack as microstation utility VS PondPack as stand-alone program: Pros/Cons?
Hello Brian, The basic difference between the standalone version of PondPack and that of Microstation integrated PondPack version is the ability to work in Microstation platform. The tools and modeling capabilities of Standalone and Microstation integrated versions of PondPack are same, but with Microstation integrated version you can use the Microstation drafting tools to print/layout the models. When you are using the standalone version of PondPack, you can export the model in formats like .dxf and shapefiles. Here are modeling capabilities of PondPack which are same for Microstation and Standalone versions. www.bentley.com/.../pondpack For storm water modeling we also have CivilStorm, which should include Pond Design, please go through the link mentioned below, then you can decide which solution to go for based on your requirements. www.bentley.com/.../civilstorm
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Wiki Page: "The root sought in BISECTWIN is not sufficiently closed to the estimated root"
Applies To Product(s): HAMMER Version(s): 10.00.xx.xx, 08.11.xx.xx Area: Analysis/Computation Original Author: Terry Foster, Bentley Technical Support Group Problem Warning message: "The root sought in BISECTWIN is not sufficiently close to the estimated root." "There is no convergence for the solution of a variable-speed pump." Product: HAMMER V8i Area: Analysis/Computation Solution This message is related to the general instability in the model. It is dependent on the system. Things to check include pump settings and demands in the system. If the reservoir is cut off there is no boundary element in the model. If pumps are trying to satisfy a small system demand, they may not be operating at the optimal operation point on the pump curve. Also, if there is a Discharge to Atmosphere element, make sure the input is correct, particularly for the "Pressure Drop (Typical)" and "Flow (Typical)" fields.
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Wiki Page: Access (ie. permission) required to install, register and run Bentley Hydraulics and Hydrology products
Product(s): WaterGEMS, WaterCAD, HAMMER, SewerGEMS, SewerCAD, StormCAD, CivilStorm, PondPack Version(s): 08.11.XX.XX and 10.00.00.XX Area: Installation Note: The following applies to all Bentley Hydraulics and Hydrology products. What level of Windows permission/access is required for installation? To install the program, the user would need administrative access. What is the level of access required to run the product? To run the program, they can be a limited user (ie. administrative access is not required). What folders do the users need permission to read/write to? C:\Documents and Settings\username\Application Data\Bentley\ C:\Documents and Settings\username\Local Settings\Application Data\Bentley\ C:\Documents and Settings\username\Local Settings\Temp Note: Normally any limited user has read/write access to their own profile on the C: drive In Windows 7, 8 and 10 it is "C:\Users\username" What registry hive do users need permission to read/write to? HKEY_CURRENT_USER\Software\Bentley\ See Also "Error writing to file...Verify that you have access to that directory" Installation What is the installation order for the WaterCAD, WaterGEMS, SewerCAD, SewerGEMS, CivilStorm, StormCAD, CulvertMaster, FlowMaster, or PondPack files? How do I download WaterGEMS, WaterCAD, HAMMER, SewerGEMS, SewerCAD, CivilStorm, StormCAD, PondPack, FlowMaster, CulvertMaster Error opening or creating project: Attempted to read or write protected memory "This library file cannot be edited. It may be read-only or you may not have rights to its folder ... System unauthorized access exception: Access to the path " " when closing a Haestad application [Solution ID#: 500000070247]
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Forum Post: RE: PondPack as microstation utility VS PondPack as stand-alone program: Pros/Cons?
Just to add a few more points to Sushma's response: - There aren't any additional calculation/modeling capabilities when working in MicroStation mode. Just the ability to take advantage of the MicroStation environment as far as plan view navigation, layout of entities and printing/visualization. If you don't need to take advantage of those things or if you're not familiar with MicroStation, the Standalone environment would be easier to use. - MicroStation integration provides more accurate drawing layout, but if you already have model data in a CAD file (or any other data source), that data can be converted to PondPack model elements with PondPack's ModelBuilder feature. For example if you have the polygons for catchment areas, you can import those as PondPack catchments very easily. ModelBuilder is available in all platforms, including Standalone. - Working in the MicroStation integrated mode has the added benefit of better printing capabilities within the same application. However, in Standalone, you can also add a CAD file (among others) as a background layer, to trace over, or to display other linework. You could then print from within the Standalone platform - You can move between platforms. For example you could do most of your modeling with in the Standalone version, then when needed, open the model in PondPack for MicroStation. - There is only one installation for PondPack, which always installs the "standalone" version, and will detect if a compatible version of AutoCAD or MicroStation is installed and will integrate with it. You'll see a separate desktop short for "PondPack for MicroStation". - All licenses of PondPack include the ability to integrate with MicroStation (it is not an extra cost) See more: CAD Functionality in Standalone as an Alternative to AutoCAD or MicroStation Integration
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Wiki Page: Where are the ModelBuilder template (ie. seed) files stored?
Product(s): WaterGEMS, WaterCAD, HAMMER, SewerGEMS, SewerCAD, StormCAD, CivilStorm, PondPack Version(s): 08.11.XX.XX and 10.00.00.XX Area: Modeling Problem Where are the ModelBuilder template (ie. seed) files stored? [Problem ID#: 70341] Solution In Windows 7, 8 and 10 the template (ie. seed) files containing default ModelBuilder settings are in the following directory. C:\Users\AppData\Roaming\Bentley\[ProductName]\8\ [Solution ID#: 500000087623] See Also Error while editing the Modelbuilder.xml file with the third party application Building and updating a model using ModelBuilder Importing A CAD (eg. DXF or DGN) Drawing Using ModelBuilder [TN]
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Forum Post: HAMMER pump shutdown followed by pump startup
How to simulated in Hammer a pump shutdown and subsequent pump startup event (e.g 80 seconds after pump shutdown the pump is kicking back in) in a sewage pumping station?.
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Wiki Page: Calculation Error: Access to path C:/temp/bentley/"program name"/xxxx is denied
Applies To Product(s): WaterGEMS, WaterCAD, SewerGEMS, SewerCAD, CivilStorm, StormCAD, HAMMER, PondPack Version(s): 08.11.xx.xx Area: Calculations Original Author: Scott Kampa, Bentley Technical Support Group Problem Description When calculating any model, the following message is generated: Calculation Error: Access to path C:/temp/bentley/"program name"/xxxx is denied Steps to Resolve Delete the files in the temp folder This can occur if there is an issue with a file in the temp folder. Note that the path to the temp folder may be different on different machines. Close the program and browse to the temp folder. Delete the items in the folder. Reopen the program and compute the model. The error message should no longer occur. Delete all the files except the files necessary to run the program Browse to where you files are located and delete all the output files except those necessary to run the model. The necessary files for the Haestad hydraulic programs can be found in this wiki . Save the file to a shorter file path For example, if the file path was "D:\ \ \folder \folder \" try saving it to "D:\ \ \" Move the files to the local C: drive Take the files associated with the program and move them to a location on the C: drive
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Forum Post: "This node is orphaned. There cannot be any orphaned, active nodes in the model."
I get this message on Pondpack. "This node is orphaned. There cannot be any orphaned, active nodes in the model." I have a post condition where the runoff enters the basin and stays there permanently.
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Forum Post: Modelling Inlet Works of a Treatment Plant
Hi, I am struggling to make sense of the oputs of my model related to pipe elevations (effectively a weir in a wet well). I want to model pumped pressure pipes coming into a wet well with scenarios for various inflows to check if the weir will overflow. I have tried setting the elevation on the overflow pipe above the HGL but SewerCAD solver doesn't seem to pay attention to this even though the incoming hydraulic grade line to the wet well is more than 1m below, the hydraulic grade on the outlet somehow jumps this up to the weir level condition I created and has it overflowing down the pipe. This doesn't make sense. I then went further to try create a condition on the HGL of the wet well, and I made the downstream pipe closed if it is below the HGL. That doesn't change anything either. I like to point out that I have tried to model this condition using a manhole with a control structure downstream but this gave me more errors and would not solve. My manhole has two outlets which is apparently is not allowed. I then tried to model it with a pond structure, but gave me errors with the upstream manhole and outfall into the pond being connected to pressure pipe and would not solve. The first way I modelled it makes more sense in terms of the hydraulics of the plant, so any help would be appreciated.
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Wiki Page: Modeling septicity / hydrogen sulfide (H2S)
Product(s): SewerGEMS, CivilStorm Version(s): 08.11.04.54 and later Area: Modeling Background This article explains how to analyze hydrogen sulfide formation (sometimes referred to as septicity) in a sewer hydraulic model. Hydrogen sulfide forms in wastewater collection systems when anoxic conditions exist and results in corrosion, odor and toxicity problems. The rate of formation depends primarily on the strength of the wastewater as characterized by BOD concentration (Biochemical Oxygen Demand) and rate constants for the reactions which are dependent on temperature. Hydrogen sulfide in most commonly a problem in systems with long detention times in warm weather. The hydrogen sulfide calculations assume that sulfate concentration is not limiting. The calculations are based on the Pomeroy-Parkhurst equation for predicting H2S concentrations in a sewer network; they can be used to evaluate the build-up or decay of the H2S concentration in a sewer system. The sewer system can be gravity and pressure combined system consisting of conduits, ponds, channels, wet-wells, pumps, pressure pipes and junctions. For more background information, see the Help topic "Hydrogen-Sulfide (H2S) Modeling" and the video further down. Modeling Hydrogen Sulfide To analyze hydrogen sulfide formation in a SewerGEMS model, the SWMM solver must be used and various data must be input into the manholes and pipes. The primary assumption is that the solver will use the average hydraulic condition for the H2S calculations. The solver determines the average pipe flow by the total flow volume that has passed through the pipe for the simulation duration, the node H2S/BOD mixing calculations will also be based on the average flows of incoming and outlet pipes. The pipe detention time is determined by the pipe length and average flow velocity; the node detention time is determined by the average node volume and average outlet flow. As a result of these assumptions the model provides a steady result set for the network which represents the expected average changes. 1) Select the Explicit (SWMM) solver in the Calculation Options or Compute Center 2) Select "True" for the calculation option "Run Hydrogen Sulfide Analysis" 3) For each manhole, enter: H2S (Local Inflow) BOD (local inflow) Usually, there is very little H2S in the inflow but the presence of BOD (biochemical oxygen demand), along with sulfate, leads to the formation of H2S. For domestic wastewater, the BOD concentration may be on the order of 200 to 300 mg/L while for industrial waste, it can vary widely. 4) For each pipe, enter: Temperature H2S Flux Coefficient H2S Loss Factor 5) For wetwells, enter: H2S (Local Inflow) Temperature Reaction rate BOD (local inflow) 6) Compute the model and view the computed H2S and BOD concentration in the "Results (H2S)" section of the properties. H2S forms in link elements (conduits, pressure pipes and channels) and is a function of temperature. The temperature default value is 20 deg C. The H2S flux concentration is on the order of 0.0003/hr while the H2S loss rate is on the order of 0.9. These values need to be calibrated for local conditions as there can be a great deal of variation. For pressure pipe and inverted siphons, there is no loss coefficient as H2S gas cannot leave the liquid phase. For wet wells, the Reaction Rate should be on the order of 0.2/day. (Please visit the site to view this video)
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