Applies To Product(s): Bentley StormCAD, Bentley SewerGEMS, Bentley SewerCAD, Bentley CivilStorm, Bentley WaterGEMS, Bentley WaterCAD, Bentley HAMMER Version(s): 08.11.xx.xx Environment: N\A Area: Modeling Subarea: N\A Original Author: Scott Kampa, Bentley Technical Support Group Error or Warning Message When trying to open a model files, a message is displayed that that file could not be found that appears to point toward the temp directory. The message is similar to: C:\Users\(user name)\AppData\Local\Microsoft\Windows\Temporary Internet Files\Content.IE5\xxxxxxx\model.stsw.sqlite How to Avoid It is possible the model file is not completely downloaded to an accessible drive, such as the local hard drive. First, browse to where the model is saved and make sure the files are not read-only and that they are available. If the models are saved to a network drive, try copying them to the local hard drive and opening them from there. If that doesn't work, try importing the database file into a new model file by opening the program and then selecting File > Import > StormCAD (or other program name) database.
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Wiki Page: "File not found" message when trying to open model file
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Forum Post: RE: PRV Setting in model
Hello Dang, You should be able to set up a control for the first two items. You would need to create a composite control with an AND statement. For the fully open valve, you can create a control that makes the valve have a status of Inactive as well. However, normal operation for a PRV will have the valve be fully open the upstream head is lower than the valve setting anyway. Regards, Scott
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Forum Post: RE: Importing TRex elevations
rmaeng, No, not directly. What I believe you'd have to do is import the file from ArcGIS online, then convert it to a shapefile or one of the other file input types that TREX can accept, and select the file from there. I just put in a enhancement for you that would add the ability for TREX to directly access ArcGIS Online files that will be considered for the an upcoming release of the software. That enhancement number is 247267 for those that are interested. Regards, Mark
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Wiki Page: General HAMMER V8i [FAQ]
Applies To Product(s): Bentley HAMMER Version(s): V8i Environment: N/A Area: N/A Subarea: N/A Original Author: Jesse Dringoli, Bentley Technical Support Group Can I open WaterGEMS/CAD V8i models? Yes. HAMMER V8i uses the same file format as WaterGEMS and WaterCAD V8i, so you can directly open the files. All 3 programs conveniently use a .wtg and .wtg.mdb file to store the model data. HAMMER V8i can also directly open WaterGEMS/CAD V8 XM models. What is HAMMER's calculation engine based upon? HAMMER uses the Method Of Characteristics. What kind of demands should be used as the initial conditions of a transient simulation? Typically, you should run a transient simulation for the maximum and minimum demand hours for each of the development conditions (network and demand points) under consideration. Are pipe bends (vertexes) used in the force calculations? No, currently they are not considered. If you need to study the effects of transient forces (X/Y/Z) on a pipe with vertexes, you should consider replacing the bends (vertexes) with junctions. When I create a graph under View > Graphs, this seems to only show the initial conditions. Where can I view detailed graphical results of the transient simulation? The transient results are viewed in the Transient Results Viewer, located under the Analysis menu. The amount of results included in here is determined by the report period, report points and "generate animation data" settings, under Analysis > Calculation Options > Transient calculation option How do you define the starting conditions of the transient simulation? The starting conditions of the model before a transient occurs are defined in one of two ways. First, you can invoke the WaterGEMS steady state solver (Analysis > Compute initial conditions) to calculate them for you, based on the demands, boundary conditions and other element attributes. This is the same solver that Bentley WaterCAD and WaterGEMS use. The transient solver then uses the computed flows and hydraulic grades as the starting conditions. Alternatively, you can define your own starting conditions (flow and head) by choosing "true" for the attribute called "specify initial conditions?" in the transient calculation options (Analysis > Calculation options.) When doing this, the transient solver will no longer use the head/flow computed by the "compute initial conditions", but instead will use the head and flow values that you must enter in, in the "transient (initial)" section of each element's properties. Note that if you want to slightly modify some computed initial conditions, you can copy them over to the user defined initial conditions fields first by using the "copy initial conditions" tool (under the Tools menu) and then alter them as you see fit. How can I view extended transient results, such as pump speed, air flow of a CAV, gas volume of a hydropneumatic tank, etc, for each timestep? First, enter a number for the "Report period" attribute of an element. This represents how often the results will be saved for. For example, a report period of '10' means that results will be shown at every 10 timesteps. Make sure text reports are enabled in the transient calculation options. Now, when you compute initial conditions, extended results will be displayed, under Report > Transient Analysis Reports > Transient Analysis Detailed Report. Scroll down to the bottom to see a table of data for the element(s) with a report period. How can I generate a graph of the various extended results seen in the Detailed Report, when using a report period for certain elements? (such as hydropneumatic tank, air valve, pump) See the following link for details: http://communities.bentley.com/products/hydraulics___hydrology/w/hydraulics_and_hydrology__wiki/11111.generating-graphs-from-extended-results-in-detailed-report.aspx I am using FCV, PRV and PSV valves in my model, but they do not seem to be working during the transient simulation, per the setting I have entered. Why? The pressure reducing / pressure sustaining / flow control properties of these valves are only used during the initial conditions calculation. This is because HAMMER assumes that during the transient event, these valves cannot react quickly enough to the changes in flow/pressure. If you are running a long transient simulation and need to model the effects of these valves, you'll need to use an operating rule on the valve to close them. Can you use simple or logical controls during the transient simulation? No, the controls that you enter under Components > Controls only apply to the initial conditions calculation. To control elements during the transient simulation, you'll need to use configuration in the individual equipment (such as closure time for the check valve node) or operating rules (such as the pattern of time vs. relative closure for a valve). I have entered controls under Components > Controls but they do not seem to be working during my transient simulation. Why? These controls only apply to the initial conditions calculations (steady state or EPS), not the transient simulation. If you need to control things during the transient, you must use the options seen in the properties of the various transient elements. For example, an operating rule for a TCV valve or the time delay until shutdown for a pump. What does the following user notification mean, and what is the deviation based on? - "WARNING: The wavespeed or length approximations deviate excessively from the entered values. Lengthen short pipes and/or subdivide longer pipes." See below wiki: http://communities.bentley.com/products/hydraulics___hydrology/w/hydraulics_and_hydrology__wiki/9401.aspx How can I find Water Deceleration in a Pipeline with a check valve? First, run the Initial Condition analysis and record the velocity in the pipe downstream of the check valve. Let's assume it is 4 ft/second. Next, run the transient simulation and open the Transient Results Viewer. Plot a time history graph of flow in the pipe downstream of the check valve and measure the time from when the pump turns off until the flow curve crosses the x-axis (i.e. when flow reaches zero). Let's assume it is 2 seconds. So the deceleration of the water column is 4 ft/second / 2 seconds = 2 ft/s^2. This is an average deceleration rate, which is typically what valve manufacturers provide. How does the Transient Results Viewer work and how can I use it to view my results? The Transient Results Viewer displays transient results in graph form and also can animate hydraulic grade in a profile. The "Paths (Profiles)" pulldown at the top allows you to select a profile (defined in the main user interface under View > Profiles) and then either plot or animate it. The "plot" will provide the minimum/maximum transient envelope. The "animate" button will allow you to see the hydraulic grade profile as it changes over time. This is useful to understand how certain transient inducing events affect the system as a whole. If the animate button is grayed out, make sure "generate animate data" is set to "true", in your transient calculation options. To reduce the amount of profiles available, go to View > Profiles, right click on the ones you'd like to omit from the transient results viewer and deselect "transient report path". The "Time Histories" pulldown at the bottom of the Transient Results Viewer displays end points that are available to graph. The amount of endpoints listed are determined by the "report points" option in the transient calculation options. Note that transient simulation results are available at the ends of the pipes where they meet a node element. For example, the upstream side of a pipe or the downstream side of a pump. For time histories, you can plot the head, pressure, flow, air/vapor volume and force (if you've chosen to compute transient force.) What do the different colored lines in a transient results viewer profile represent? In general, you can right click on the frame/axis of the plotted profile, select "format data" and see the names of the various plotted lines in the dropdown. For an animated profile, check the below diagram: For a plotted head envelope: Solid black line - physical elevations Dashed black line (or solid orange line if a pressure plot) - Initial conditions head Solid red line - maximum transient head Dashed blue line - Minimum transient head Red line at top - Max vapor/air volume Dashed yellow line - vapor pressure (as a reference) How can I add a new material such as HDPE to the material library? Go to Components > Engineering Libraries and click the plus sign next to "Material Libraries" Right click MaterialLibrary.xml and choose "add item" - a new material entry will appear at the bottom of the list. Right click this new material entry, choose rename and enter the name (such as 'HDPE'). On the right side, enter the friction coefficients, Young's Modulus and Poisson's ratio for your new material, then click close. Note: The Young's Modulus and Poisson's ratio are only necessary if you need to use the automatic wave speed calculator tool, under Tools > Wave Speed Calculator. If you would like to create a new engineering library (xml file) instead of altering the default MaterialLibrary.xml, simply right click on "Material Libraries", choose "create library", choose a location to save the file, then repeat steps 2-4 above, replacing 'MaterialLibrary.xml' with the name of your library. What is the difference between the "Elevation" and "Elevation (inlet/outlet invert)" fields in the properties of a reservoir? The "Elevation" represents the water surface elevation and the "Elevation (inlet/outlet invert)" represents the invert of the pipe that attaches the reservoir to the system. Pressure at the reservoir location is determined by the difference between these values. How can I model a shut after time delay pump that has neither a check valve or control valve? When using "shut down after time delay" transient pump type, you must select either "control valve" or "check valve" as the Pump valve type. If you do not want a check valve or control valve, select "Control Valve" As the pump valve type and enter a large number such as 9999999 seconds, as the "Time (For Valve to Close)". How can I plot multiple time histories in the same graph or multiple profile plots on the same profile? Natively there is no direct way to do this with the Transient Results Viewer. However, you can do it using the below process. This is useful in cases where you'd like to compare transient profile/time series results between scenarios. 1) Open time history graph (or profile plot) number 1 2) Right click in the middle of the graph and choose Save As > HAMMER graph - save the .grp file somewhere 3) Close graph (or profile plot) number 1 and go to File > open and reopen it 4) Right click on the frame of the graph and choose "copy data" 5) Open graph (or profile plot) number 2, right click on the frame and choose "paste data (+)". Note: you may have to adjust the Y axis scale if the pasted data doesn't fit in graph number 2. Why do I need to enter a "nominal head" and "nominal flow" when modeling a pump startup event? When modeling a pump startup event by using the "pump start - variable speed/torque" transient pump type, the "nominal head" and "nominal flow" represent the operating point of the pump once it has started up and reached full speed. The reason why this is needed is because HAMMER uses a special 4-quadrant pump curve during the transient simulation (not your pump definition) which has points that are relative to the nominal operating point. So, since the initial head/flow are zero in this case, HAMMER needs you to enter the nominal operating point, so it's able to use the 4-quadrant pump curve. Typically you would simply compute a steady state simulation with the pump on, record the operating point, turn it back off, then use that for the nominal head/flow. What is the difference between "Constant Speed - Pump Curve" and "Constant Speed - No Curve", for the transient pump type? See below Support Solution Article: Differences between Constant Speed transient pump types . See Also Product TechNotes and FAQs Licensing TechNotes and FAQs Haestad Methods Product Tech Notes And FAQs External Links Bentley Technical Support KnowledgeBase Bentley LEARN Server
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Forum Post: RE: I need estimate the pressure in impermanent regime due to the fall a pump when this started to operate (Shut Down)
Hello Felipe, Are you modeling a pump shut down in HAMMER? If that is the case, you would want to set the Transient Pump Type in the pump properties to "Shut Down After Time Delay". There are a couple of sample models that model a pump shut down event. These samples can be found at C:\Program Files (x86)\Bentley\HAMMER8\Samples. Sample models that have a pump shut down include Sample2.wtg, Air_Valve_Example.wtg, and Hydropneumatic_Tank_Example.wtg. In these samples you can see the general setup for a pump shut down event. There are a number of sources that might be useful for you when using HAMMER. Our TechNotes and FAQs page have a number of topics on HAMMER, including on the protection devices HAMMER uses. The HAMMER V8i FAQ has a lot of good general information on using HAMMER and viewing results. Regards, Scott
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Forum Post: RE: I need estimate the pressure in impermanent regime due to the fall a pump when this started to operate (Shut Down)
Hello Regards I need estimate the pressure in impermanent regime due to the fall a pump (SHUT DOWN), but in the moment when this started to operate. Then, when the pump is close to find its operation point, occurs the shut down. It's model is different from modeling only a shut down. Felipe.
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Forum Post: RE: Managing Many Scenarios, How do you keep it 'tidy'?
Tom Walski You mention stripping out everything including alternatives that are no longer needed. How do you accomplish that if you have many levels of children? It seems that you can't delete an alternative or scenario without deleting everything under it. So if your desired model is many levels down in the hierarchy, how can you get rid of everything 'above' it?
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Forum Post: RE: Managing Many Scenarios, How do you keep it 'tidy'?
If you are deleting the base scenario/alternative which is no longer needed, then that will delete children scenarios as well, which might be required to you. That’s why Dr. Walski mentioned about creating new separate files for different studies. If you are pushing the software to its memory limit, then it may slow down as well.
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Forum Post: RE: Control override and initial setting
Could you please elaborate the issue by giving more explanation, which output is not exactly matching with the real network? Do you want to override the pressure values? Do you mean to ask that what adjustments can be done to match the results with the real model?
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Forum Post: RE: Control override and initial setting
If you're looking to force a pattern of pump on/off, set the property "Is variable speed pump?" to true, then select Pattern Based as the VSP Type. You can then configure a pattern of relative speed that the pump will follow (0 = off, 1.0 = full speed) It may be worth considering that other things in the model might be the cause of the discrepancy.
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Forum Post: Watergems node demand
I have loop network model with pipes and junctions. Initial Junction water demand is zero. If I have total demand available for the network please explain step by step, how to allot water demand to each junction or node with different method.
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Forum Post: RE: PRV Setting in model
Thanks Scott, It looks reasonable for control rule that you mentioned, but it just only work in case that P < 20 and then it is fully open. In some cases I also got the problem when set logical control rule. So could you give me example that running successfully in those cases in logical control? Regards, Dang
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Forum Post: Surge Anticipator Valve (SAV): No discharge flow reported after minimum threshold pressure reached.
Hey, I have an SAV in my transient model, that, when a minimum pressure threshold is reached, reports no flow through it. I have set up a tee off of the main discharge header to put the SAV off of. Does anyone know why this is, or has anyone experienced this? Thanks, Mike
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Forum Post: RE: Control override and initial setting
Sushma Choure, Yes, I would like to using Pressure at downstream at pumps to override that historical data. Is it possible? Jesse Dringoli, With the pattern based as VSP, I didn't have pump's relative speeds. Should I convert Pressure to Relative speed by Affinity Law for Variable Speed Pump?
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Forum Post: RE: Control override and initial setting
You should probably model what's in the system - if the pumps are simply turning on and off and operating at full speed when on, use 1.0 for On and zero for off, in the pattern. If the pumps are variable speed and maintain a downstream set pressure, then model them as Fixed Head variable speed pumps with the appropriate hydraulic grade setting and they will automatically calculate the speed needed to achieve that set pressure. If the pump on/off is based on something like a tank level but pressure results are not matching field observations, the model may need to be calibrated. There are a number of possible reasons why the results could be different, such as stuck valves, pipe roughness differences, demand differences, etc. Forcing the pumps to follow the field observations may not result in an accurate depiction of the system.
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Wiki Page: Pump shut down: speed vs. torque and Pump Start Up
Applies To Product(s): Bentley HAMMER Version(s): 08.11.XX.XX Environment: N/A Area: Layout and Data Input Subarea: Original Author: Terry Foster, Bentley Technical Support Group When I run a pump shut down using the pump shut down after time delay setting, the residual flow through the pump(s) is different from when the pumps is set to the variable speed/torque pump type. What is the difference between these two types of pumps? Background The difference between the pump shut down after time delay and the variable speed/torque pump type options are the shut down after time delay assumes that the electrical torque applied to the pump impeller suddenly drops to zero, whereas with the variable speed type, you enter the pattern of pump impeller speed so you are directly controlling the speed of that impeller. With the shut down after time delay, the impeller will take some time to spin down once power is cut based on the inertia/momentum. Steps to Accomplish If you wanted to have the variable speed/torque pump type act like the shut down after time delay pump type (cutting off the power instead of having to manually control how the speed changes), then you could set it to use "Torque" as the control variable instead of "Speed" (this is the default). This is done in the pump properties. 2. If you want to use the variable speed type (instead of variable torque), you would first need to decide how long it takes for the pump impeller to slow to a stop, after it shuts down. If you need help in doing this, you could do a trial run using the "Shut after time delay" transient pump type with a number in the "Report Period" field. After computing the transient simulation, look at the bottom of the transient analysis details report to see the pump speed over time. 3. Next, you will need to define a transient pump pattern (Components > Patterns) based on that delay and when you want the pump to restart. You'll need to decide how long it takes for the pump to turn back on as well. In the pattern, 1.0 represents full speed and 0.0 represents fully stopped. Model the pump as being on in the initial conditions, set the transient pump type to variable speed, then select the pattern that you created.
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Wiki Page: How to globally edit certain elements in a FlexTable?
Applies To Product(s): Bentley WaterGEMS, Bentley WaterCAD, Bentley SewerGEMS, Bentley SewerCAD, Bentley CivilStorm, Bentley PondPack, Bentley HAMMER Version(s): 08.11.xx.xx Environment: N/A Area: Layout and Data Input Subarea: Original Author: Scott Kampa, Bentley Technical Support Group How To How can a user globally edit only certain elements in a flextable? Background There are cases when a user may want to globally edit only certain elements in a FlexTable. In such a case, you need to use a filter to remove some of the elements from the FlexTable. Below are steps to do this. Steps to Accomplish Option 1 To filter a Flextable, open the element Flextable and right-click on any column header. Next, choose Filter > Custom. This will open the Query Builder dialog. Next, you will need to create the query you want to filter the FlexTable with. For instance, you may want to only view the pipes with a diameter of 250 mm. If such a case, you would search the Fields table on the left for "Diameter". Double-click this and it will appear in the section at the bottom of the Query Builder dialog. Next, select the operator, such as "=". Next, click the Unique Values button in the upper right and then double-click the value you want to filter by. When you are done, the Query Builder dialog will look similar to the screenshot below NOTE: If you want to filter by more than one item, you can select the "AND" operator from the middle of the dialog and then go through the process above once more. Once you click Okay, the filter will be applied. The FlexTable will now look similar to the screenshot below. Note that it says "FILTERED" in the lower right of the FlexTable. In the lower left, if says that only some of the elements are displayed (in the screenshot above, "4 of 17 elements displayed"). These are indicators that a filter is applied. Now when you globally edit the FlexTable, only the elements that are displayed will be changed. All other elements will be left with their original values. To do this, right-click on the column header you want to change and choose "Global Edit". A new dialog will open. Choose the operator. For numerical fields, like diameter, you have an option to "Set" and use mathematical operators, like Add and Multiply. For text fields, only the Set option is available. Choose the operator and enter a value and the value in the FlexTable will change. To remove the filter, right-click on any column header once more and choose Filter > Reset. This will reset the filter and display all elements. Option 2 Another way that you can filter and edit only some elements is via the steps below: 1) Open the Selection Set manager (View > Selection Sets) and highlight the selection set you want to view with a single left click on the name. The selection set name should now be highlighted in blue. 2) Right-click on the selection set name and choose "Select in Drawing" from the pop-up menu. Only the elements in the selection set will be highlighted in the drawing pane. 3) Right-click in the drawing pane and choose "Edit Group" 4) Choose the FlexTable you want to view the selection set with and click the "Ok" button. When the FlexTable opens, only the selected elements will be displayed. You can then globally edit the FlexTable so that only these elements will change. Option 3 Similar to the Selection Set option, you can simply manually highlight elements in the drawing. Hold down the control button on your keyboard to select more than one item or use the selection tools located under the 'Edit' menu. You can then right click in the drawing pane and select Edit Group. The rest of the steps are the same as Option 2 above. This method can be less precise then using the other methods, but can be useful if you know which elements you want to change
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Forum Post: RE: PRV Setting in model
Hi Scott, It works now, I'm sorry that I forgot to consider the case that pressure at downstream higher than pressure setting, that time PRV will close immediately! Regards, Dang
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Wiki Page: How do I append a prefix to element labels based on a selection set of elements?
Applies To Product(s): Bentley WaterGEMS, WaterCAD, HAMMER, StormCAD, SewerCAD, SewerGEMS, CivilStorm Version(s): 08.11.XX.XX Environment: N/A Area: Output and Reporting Subarea: Original Author: Mark Pachlhofer, Bentley Technical Support Group Problem How do I append a prefix to element labels based on a selection set of elements? Steps to Accomplish StormCAD, SewerCAD, SewerGEMS or CivilStorm Select all the elements you want in your selection set on the drawing pane while holding down the control button or by using the following options found in this wiki technote With the elements in your selection set highlighted in the drawing go to View > Flextables and right click on the flextable that you are going to open the selection based on then choose "Open on Selection" Right click on the grey Label field column header in the flextable and choose the "Relabel" option 4. Change the 'Relabel Operation' to "Append" and enter either the prefix or a suffix to be appended. Click "Ok" when you are done. 5. Repeat these steps for each group of elements you need to append a label to See Also Sorting and relabeling a flextable based on upstream-downstream order
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Forum Post: RE: I need estimate the pressure in impermanent regime due to the fall a pump when this started to operate (Shut Down)
Hello Felipe, If I am understanding the issue correctly, you want to model a pump starting up and then have it shut down again after it reaches its operating point. There are a couple of ways that you can model this. The first would be using the "Pump Start - Variable Speed/Torque" option for the Transient Pump Type. This allow you to enter an operating rule with the pattern that the pump will follow. The pump will start in the Off position for the initial conditions. You will need to enter a nominal head and flow value that the program can use to identify the pump curve that will be used. The operating rule can also include the pump shutting down again, so the pump start up and shut down can occur in a single scenario. You can find details on modeling a pump start up at the following link: communities.bentley.com/.../3276.modeling-a-pump-start-up-transient-event-in-bentley-hammer-v8i-tn Another possible solution would be to model the pump start up and the pump shut down in separate scenarios. If the pump will be on long enough that an transient from the pump start up will have dissipated, this would be a suitable operating case. You would model the pump start up in one scenario and analyze the results. In another scenario, you would model the pump shut down. If this doesn't help with the issue, I will need some additional details on what you are trying to model. Regards, Scott
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