See related article: Fire flow analysis at the time of minimum pressure (EPS Fire Flow Analysis Tool)
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File: EPS Fire Tool for WaterGEMS and WaterCAD 10.02.01.06
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Wiki Page: Fire flow analysis at the time of minimum pressure (EPS Fire Flow Analysis Tool)
Product(s): WaterGEMS, WaterCAD Version(s): 10.00.00.55 and Later Area: Modeling What it Does The EPS Fire Flow Analysis tool automates specific fire flow results. It provides a way to run a range of flows on each fire flow node, only at the time of minimum pressure from an EPS, and run the full EPS up to that point. Benefits Some regulatory agencies require this type of analysis (eg. Australia). Applicable Products and Version The EPS Fire Flow Analysis tool is available for the following products and versions. WaterCAD and WaterGEMS version 10.00.00.55 and later How to Access First, make sure you have one of the above products and versions installed. Click here to see how to determine the version you are using. Next, Determine if you are using the product in 32-bit or 64-bit mode. To check, go to: File > Help > About WaterGEMS (or WaterCAD) The bottom of the dialog will show either 32-bit or 64-bit. Download : Version Download Link 10.00.00.50 & 10.00.00.55 Download 10.01.00.72 Download 10.02.00.43 Download 10.02.01.06 Download 10.02.02.06 Download Install : 1. Download and extract the following .zip file: 2. Copy the extracted "Haestad.EPSFireFlow.exe" files as shown below. Copy the file from the folder “x86” to the following folder: C:\Program Files (x86)\Bentley\ \ Copy the file from the folder “x64” to the following folder: C:\Program Files (x86)\Bentley\ \x64\ 3. Run the "Haestad.EPSFireFlow.exe" file from that location. How to Use The tool is very simple to use and provides minimal options. When running the "Haestad.EPSFireFlow.exe" file the following dialog will appear. Note: if there is an issue starting the tool then try right-clicking on the executable file and selecting “Run as Administrator”. 1. Select the model Click the Open button to select a WaterCAD or WaterGEMS project to use for the analysis. Once the project is open, there are options that must be specified before calculating the EPS Fire Flow. 2. Select the scenario(s) a. Click the Scenarios button to display the "EPS Fire Flow Scenario Selection" dialog. b. Select at least one EPS scenario, and then click OK. 3. Choose a selection set Choose a selection set from this dropdown list to use for the EPS fire flow analysis. The junctions and hydrants in the chosen selection set will be included in the analysis. Each of these junctions and hydrants will have the fire flows applied (during the time when the pressure is lowest) for each fire flow included in the range. Note: This option is required. The number of fire flow nodes in the selection displays to the immediate right of the drop-down box. The number of nodes includes both inactive and active nodes. The “Is Active?” state of the node is determined during calculations and inactive elements are ignored. 4. Specify how fire flows will be applied In the "Apply Fire Flows By" dropdown, specify if the fire flows will be applied by adding to the baseline demand or if they will replace the baseline demand. 5. Select a range type Range : This allows a Minimum, Maximum, and Increment to be entered to establish the range of flows that will be tested for each fire flow node in the selection set. The minimum must be greater than 0.0 and less than the maximum flow. The difference of the minimum and maximum flows must be equally divisible by the increment. User Defined Flows : This will establish the range of flows that will be tested for each fire flow node in the selection set. When this is selected then flows can be manually added and deleted in a tabular format. Calculation Steps To calculate the EPS fire flows click the Compute button to the right of the Open button in the toolbar. Here are the steps performed by the tool. Calculate each scenario. Determine the times during the EPS scenarios when active node in the selection set is at its respective minimum pressure. Calculate a hydrant flow curve for all active nodes in the selection set for the scenarios selected. Each hydrant flow curve will be created at the time each node is at its respective minimum pressure. Use the hydrant flow curves to find the residual pressures for each of the user-specified fire flow values, for each combination of the specified scenarios, nodes and times. See: Help Topic “Hydrant Flow Curve Editor" Data Validation The data is validated when computing. An error will appear if any of the following are true: One or more selected scenarios is not EPS. There aren’t any active junctions or hydrants are in the selected fire flow nodes selection set The minimum fire flow is less than zero or greater than the maximum fire flow The maximum fire flow is equal to orless than minimum fire flow Increment is zero or not an exact factor of the difference between the min and max One or more scenarios fail to compute (An initial check is made by running each selected scenario as-is). Results The results are presented in a table once the calculation is successfully completed. If the validation fails, no results are displayed until the issues reported are resolved. The first three columns are always available showing the scenario label, the fire node label and the time at minimum pressure. The remaining columns are based on the flow range specified. The hydrant flow curves (created for each combination of scenario, node and time) are used to interpolate the residual pressure for each flow specified in the fire flow range. If the interpolation returns a negative pressure, (N/A) is shown in the table. Otherwise, any pressure greater than zero is displayed. Units The units used in the tool are based on the settings of the open project. You can change units by right-clicking the unit next to the minimum, increment and maximum fields on the main dialog and clicking “Units and Formatting”. You can change the units of pressure in the results table by right-clicking the column header and clicking “Units and Formatting”. Other Notes No changes are made to the project opened. When closing the tool or opening a different project, the project that was previously opened (if there was a project opened) is not saved. See Also EPS (Extended Period Simulation) Fire Flow Analysis Understanding Automated Fire Flow Results
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File: EPS Fire Tool for WaterGEMS and WaterCAD 10.02.02.06
See related article: Fire flow analysis at the time of minimum pressure (EPS Fire Flow Analysis Tool)
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Forum Post: RE: Link has adverse slope and flooding not reporting
1) Upon closer inspection, it appears that the adverse slope warning is due to the downstream wetwell. When the conduit is configured to automatically set the invert to the stop node, it picks up on the wetwell base elevation (-3.41 m), but it appears that the warning message in question is incorrectly using the minimum elevation (-3.0 in your case), hence you get the adverse slope warning. I have reported this to our development team as Defect #1060214 . They will prioritize and investigate for a future release. In the meantime, you can either ignore the message, or set the wetwell minimum elevation to -3.41 m). 2) I can confirm that the lack of overflow at MH31 and MH32 is because the numerical solver ignored overflow in favor of stability, because the overflow would be due to backwater effects from the downstream wetwell water level. If you change the LPI coefficient to 5.0 for example, you will start to see overflow (graph the HGL, rim elevation and overflow together to see), but the results are less stable and will require further tweaking of advanced calculation options per this article, if you want to account for overflow. See: Zero overflow at manhole despite HGL above rim. Troubleshooting unstable SewerGEMS and CivilStorm results using the Implicit solver
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Wiki Page: Change graph and profile appearance using Chart Options
Product(s): WaterGEMS, WaterCAD, HAMMER, SewerGEMS, SewerCAD, StormCAD, CivilStorm Version(s): V8i, CONNECT Edition Area: Output and Reporting Problem How can I change / edit the appearance of a graph or profile, such as the line style and some axis data? Solution It is possible to make some changes to the graphs and profiles using the Chart Options function. These changes can then be saved as the default setting (for WaterGEMS, WaterCAD and HAMMER). To access the Chart Options function, create or open a graph or profile. Then click the Options button and choose Chart Options. In the Chart Option dialog, you can see all of the available options. Most of what you will do to the appearance of the graph or profile will be from the Chart tab located in the upper left of the Chart Options dialog. From here, you can change appearance of the data, the appearance of the graph or profile, and some of the information for the axes. As an example, if you wanted to change the way the lines in the graph look, you can select the Series tab (as shown above) and click the Change button. This will open the dialog below and allow you to change the graph or profile appearance. Note that Chart Options is currently a third-party program and not all features are currently available. Some the options above are available though. Select the option you want and click OK. When you click okay again to close out of Chart Options, the graph or profile appearance will change. These general steps are the same for other options in Chart Options as well. This will save the appearance of the graph or profile when it is open, but other graphs and profiles will not use the same formatting. To make it so other graphs/profiles use the same formatting, click the Options button and choose Save Chart Options As Default. This will save the current chart options settings as the default for future graphs/profiles. NOTE: this is currently not available in SewerGEMS, SewerCAD, CivilStorm or SewerGEMS as of version 10.02.02.04 ( reference ) Again, not all function in Chart Options are available or available to save as the default. Additional functionality will be included in future releases of the products. How to Customize the Grid Color 1. Go to Chart Options > Axes > Ticks 2. Select the Left Axis (from the left pane) > Grid > Color > Select new color > OK. 3. Close the Chart Options dialog and the graph/profile will update with the change. See Also Changing the color of a bar, dot or line series in graphs How do I change my the chart options on my graphs so they start at a certain time? Changes to a graph's chart options aren't being retained
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Forum Post: RE: How to Set Default settings for Hydraulic Profile.(not Engineering Profiles)
I have added a note about this to the following article from our Wiki: Change graph and profile appearance using Chart Options
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Forum Post: RE: Pumping flow- Using SWMM Solver In sewer gems connect Edition
Mohammed, The differences in results between the two pipes may be due to attenuation, instability, or some other factor. As for the reason for the reverse flow - this may be due to numerical instability or mass balance error. In the SWMM Calculation Summary, do you see a high number for the "Not converged (%)", or the routing continuity error in the routing tab? If so, this means that you'll need to either fix data entry issues (check the User Notifications list) and/or adjust the calculation options to achieve better stability. For example you may need to try a smaller value for the Routing Step in the calculation options, which can be especially helpful in models with fast-cycling pumps and/or control structures (which I am guessing you may be using with your tanks). You can read more instability troubleshooting tips in the following article from our Wiki: Troubleshooting unstable SewerGEMS and CivilStorm model results using the Explicit SWMM Solver If this does not help, please provide a copy of the model for review: Sharing Hydraulic Model Files on the OpenFlows Forum
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Wiki Page: Batch run in HAMMER
Applies To Product(s): HAMMER Version(s): CONNECT Edition, V8i Area: Modeling Original Author: Scott Kampa, Bentley Technical Support Group Problem How can a user do a batch run in HAMMER, to compute transient simulations for multiple scenarios at once? (so as not to have to wait for each one) Solution Starting with the V8i SELECTseries 5, Bentley HAMMER now has the ability to execute batch runs on multiple scenarios, similar to the functionality found in WaterGEMS and WaterCAD. Scenario Batch Run File Starting with HAMMER CONNECT Edition Update 2, a new import and export feature has been included in the Batch dialog. You can select a set of scenarios in a batch and export these selections out to a Scenario Batch Run (.sbr) file. If you clear the batch selection, you can then quickly select them again by importing the Scenario Batch Run file again. This can be particularly useful for models with a large number of scenarios, to enable you to switch between different batch runs quickly. Initial Conditions Optimally, the user should have the setting “Always Calculate Initial Conditions” active (Analysis > Always Calculate Initial Conditions), but HAMMER will generate a prompt that will allow the user to calculate initial conditions at the prompt without needing to go back to model. Note that you cannot perform a batch run of just the initial conditions. If you need to batch run steady state or EPS scenarios, you will need to use WaterGEMS or WaterCAD. Viewing Results Results for multiple scenarios can be viewed on the same graph for Time Histories and Extended Node Data by selecting the ellipsis button next to the Additional Scenarios item in the Transient Results Viewer: If you are using an older version of HAMMER, batch run is not available and you will have to compute each scenario individually. You can then view the results from the individual results in the transient results viewer by changing the scenario. Note that you may need to reopen the Transient Results Viewer after changing scenarios. This is because different scenarios may have different active elements, and therefore, different available profiles and active elements in the time history graphs. There is also a tool based on WaterObjects.NET created by Bentley Technical Support that will allow for batch runs to be used in older versions of HAMMER. The following section has some details The following forum post has instructions on how to use this WaterObjects.NET tool, as well as a download file to obtain this: http://communities.bentley.com/products/hydraulics___hydrology/f/5925/p/94264/275526.aspx#275526 Note that this tool is not an officially certified tool or feature, so appropriate precautions should be taken. The simplest solution to the issue would be to upgrade to the latest version of HAMMER See Also Scenario and Alternative Management
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Forum Post: RE: batch compute/run
1) The batch run functionality is simply a faster way to run multiple scenarios. In some cases you may have a need to try several different surge control strategies with a large model that takes a long time to compute. So, rather than click the compute button, wait, then check back and see that the first run is done, then change the scenario and compute again, you can use the batch run function to compute all of the selected scenarios. If you search on the forum you will see several instances where users requested this for HAMMER (it was a function in WaterGEMS and WaterCAD for a long time but relatively recent for HAMMER). 2) The batch run tool in HAMMER is meant to compute transient simulations in batch. If you need to batch run steady state simulations, you will need to use WaterCAD or WaterGEMS. See related article from our Wiki, which now makes mention of this: Batch run in HAMMER
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Wiki Page: WaterGEMS and WaterCAD TechNotes and FAQs
This article provides a list of in-depth TechNotes and FAQs for Bentley WaterCAD and WaterGEMS products. To search within this page, press [Ctrl]+F. Frequently Asked Questions WaterGEMS and WaterCAD General FAQs Automated Fire Flow FAQ WaterGEMS For ArcGIS FAQ Modeling Building and updating a model using ModelBuilder Carbon Emission Analysis and Energy Cost Analysis Converting older WaterCAD/WaterGEMS files into WaterCAD/WaterGEMS V8i format and saving presentation settings Creating controls, conditions, actions and controls sets Creating formula-based User Data Extensions Energy Cost and Energy Management Flushing SCADAConnect Simulator Automatic processing of results (or other) data using an extensible data exchange framework How does the Pressure Reducing Valve (PRV) work? How does the Pressure Sustaining Valve (PSV) work? How to edit demands, unit demands, or a subset of demands globally Importing A CAD (eg. DXF or DGN) Drawing Using ModelBuilder Importing Demands From A Spreadsheet Importing Time Series Data Using ModelBuilder Modeling Air Valves At High Points Modeling a Connection to an Existing System Pump Station and Pump Combination Curves Running a Criticality Analysis Running Pipe Break Analysis Scenario and Alternative Management Setting Up Pressure Dependent Demand System head curves with no downstream storage Understanding Automated Fire Flow Results Water Model Calibration Tips Using Darwin Calibrator Using Darwin Designer Using Darwin Scheduler Using Network Navigator Using Pipe Renewal Planner Troubleshooting Troubleshooting and Understanding LoadBuilder Troubleshooting "Network Unbalanced" Troubleshooting negative pressures at pumps, junctions, & other node elements What's New What's new in WaterGEMS and WaterCAD V8i SELECTseries 2 What's new in WaterGEMS and WaterCAD V8i SELECTseries 3 What's new in WaterGEMS and WaterCAD V8i SELECTseries 4 What's new in WaterGEMS and WaterCAD V8i SELECTseries 5 What's new in WaterGEMS and WaterCAD V8i SELECTseries 6 What's new in WaterGEMS and WaterCAD V8i SELECTseries 6 with CONNECT Integration What's new in WaterGEMS and WaterCAD CONNECT Edition What's new in WaterGEMS and WaterCAD CONNECT Edition Update 1 What's new in WaterGEMS and WaterCAD CONNECT Edition Update 1 (Build 10.01.01.04) What's new in WaterGEMS and WaterCAD CONNECT Edition Update 2 What's new in WaterGEMS and WaterCAD CONNECT Edition Update 2 (Build 10.02.01.06) What's new in WaterGEMS and WaterCAD CONNECT Edition Update 2.2 – Build 10.02.02.06 See Also WaterCAD Product Information WaterGEMS Product Information OpenFlows Product TechNotes And FAQs OpenFlows Water Solutions on Bentley Website
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Forum Post: RE: residual pressure
[quote userid="1017321" url="~/products/hydraulics___hydrology/f/haestad-hydraulics-and-hydrology-forum/185983/residual-pressure/547456"]Modeling as Discharge to Atmosphere sounds like a good idea, but what if I need to keep modeling the discharge point as a tank, for purposes of monitoring the tank's water volume AND I am simultaneously interested in keeping an eye on the residual pressure at the discharge point into said tank?[/quote] If you have a reservoir (tank) that fills from the top, try the top filling tank feature by setting "has separate inlet?" and "tank fills from top?" to "True". The tank element does not report the inlet pressure, but it does report the inlet hydraulic grade, so you could add a formula-derived user data extension to calculate the pressure at the tank inlet. Note that internally this is treated as a PSV with HGL setting equal to the desired elevation where the tank fills from, so the inlet pressure will not vary. The exception would be if you use the throttling inlet valve feature (as the "from" HGL reported at the tank node would then vary), but that simulates a built-in valve that throttles as the tank gets near-full. (see details in the above article) If you want to introduce residual pressure due to the restriction at the pipe end, while still modeling the tank, you could model it as a minor loss coefficient on a short pipe connected to the tank (still using the top-fill feature, if it does fill from the top), and then monitor the pressure at the upstream junction.
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Forum Post: RE: Hammer - pump trip of reversible Francis pump-turbine
Luke, I am not aware of any plans but I will consult with our product manager.
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Forum Post: RE: LID design only works in SewerCAD - not StormCAD?
Debra, StormCAD uses the Rational Method, which computes a steady state peak flow simulation. It is well suited for pipe sizing and storm sewer design. The Low Impact Development (LID) feature is used with runoff hydrographs, which require an unsteady simulation, hence you'll need to use one of the other solvers/products such as the SWMM solver in SewerGEMS or CivilStorm. You can find more explanation in the following article from our Wiki: Can I use a low impact development (LID) controls in StormCAD?
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Forum Post: RE: Discharge coefficient,changing RPM on Pump
Hello Avin, When you don't have TCV discharge coefficient value available with you then you can calculate it using the formula provided here in the technote. Configuring TCV relative closure patterns for EPS What is the "Discharge Coefficient"? You can specify the speed of pump i.e. RPM in Components> pump definition > Transient tab > Speed (full). When you are running an EPS run in WaterCAD / WaterGEMS, pump speed i.e. RPM of pump doesn't matter, relative speed (see pump properties) is used to calculate the pump discharge along with head discharge relationship specified in pump definition. If you want the pump to start at 80% of full speed for example, you would enter 0.8 (for example a 1600 rpm pump that you want to start at 1280 rpm) Can you please explain if you are looking to model variable speed pump here, though you have mentioned its constant speed pump. This information is required for transient analysis
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Forum Post: RE: isolation valve position
Hello Mohamed, [quote userid="851837" url="~/products/hydraulics___hydrology/f/haestad-hydraulics-and-hydrology-forum/186647/isolation-valve-position"]How could I locate an isolation valve at a specific position on a pipe with a schematic drawing?[/quote] Can you elaborate on what do you mean by "specific position" of the isolation valve. The function of the isolation valve is to isolate the pipeline for maintenance in case of a breakdown or leakage condition. [quote userid="851837" url="~/products/hydraulics___hydrology/f/haestad-hydraulics-and-hydrology-forum/186647/isolation-valve-position"]Can an isolation valve replaced by another type of valves in watergems to do the same task?[/quote] An isolation valve closes the pipe for a duration. You can manually close the pipe by changing the "Status (Initial)" property to "Close". You can also try using a general purpose valve (GPV), a throttle control valve (TCV) to act as isolation valves. Can you elaborate on why you are selecting these other valves instead of isolation valves?
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Forum Post: RE: Checking of surge pressure using WaterGEMS
Hello Dina, Before running transient analysis, model needs to be hydraulically stable. Meaning you should first compute the model successfully in WaterGEMS and then perform transient analysis in Hammer. Preparing an existing model for a transient analysis in HAMMER After computing initial conditions in Hammer it is seen that results are not stable at steady state, with errors about pump cannot deliver flow and disconnected demand nodes. In your modeling case, pump is not required, there is no head available for the pump to deliver flow. If I replace pump with a junction, compute the model and open profile, you can see that pressure is achieved easily. However you might need to control / reduce the pressure in some areas by using e.g. PRV. Can you please confirm the elevations entered are correct and other model inputs? Here is learning resource guide of Hammer, for your reference. Learning Resource Guide for new users of Bentley HAMMER
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Forum Post: pump fully shutdown
Hello I am modeling a system consist of 2 pumps where I would like to know how long pump keep rotating based in it is inertia after power failure?? regards
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Forum Post: StormCad User Notification "The calculation option Structure Loss Mode must be set to EGL...
I am trying to run HGL calcs and everytime I have Calculation Option - Structural Loss Mode set to Hydraulic Grade it gives me the above error to switch it to EGL. Anyone know why this is, if this is correct for doing HGL calcs or have a work around. Thanks
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Forum Post: RE: isolation valve position
To add to Yashodhan's response: The Isolation Valve element has the advantage of associating with a pipe instead of splitting it. It can perform the same function as other valves such as a GPV or TCV in that it can open or close, but using isolation valves can reduce the number of pipes in your model since they do not split the pipe like the other valve node elements do. If you already have valve node elements like GPVs or TCVs in your model where the isolation valves should be, you can convert them to isolation valve (and reduce the number of pipes in the model) using the Inline Isolation Valve Replacement tool in Skelebrator. If you do not have the valves in the model yet but have them in an external source, such as a spreadsheet with the label and X/Y coordinates or a shapefile, you can use ModelBuilder to import them, then use the batch assign isolation valves to pipes tool to associate them with the pipes. If this does not help, then as Yashodhan said, please provide more details on what you need to accomplish.
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Wiki Page: Modeling a pump shut down transient event
Applies To Product(s): HAMMER Version(s): V8i, CONNECT Edition Original Author: Mark Pachlhofer, Bentley Technical Support Group Problem How do I model a pump shut down (pump power failure) transient event? Solution Shut down after time delay The traditional method of simulating a pump shutdown transient event is to use the Shut After Time Delay transient pump type. This assumes that the applied electrical torque drops to zero at the time that you specify for the shutdown. For more on the assumptions, check the article in the "See Also" section at the bottom of this page. Here are the steps to configure a pump shutdown event in HAMMER: 1) Set the pump Status(Initial) to 'On' 2) In the Transient (Operational) section of the pump properties set the pump type (transient) to 'Shut Down After Time Delay'. 3) Set the Time (Delay until Shut Down) property. The time you enter is the time at which the power to the pump motor is shut off. It should also be noted that a linear closure is assumed for this case. 4) Set the Pump Valve Type to check valve or control valve depending if the pump has one of these type of valves. If your pump has a control valve you'll need to enter the time it takes for the valve to close. This is the time taken for the pump discharge control valve to close after the transient simulation begins. The check valve assumes instant closure on the first detection of reverse flow. If you want neither a control valve nor a check valve, choose control valve and enter a large number such as 99999 seconds. If you want to control the closure time of the check valve use the steps from the last sentence then insert a check valve node element from your layout toolbar just downstream of the pump. See screen shot below: Note : unless you model this built-in valve, HAMMER does not assume that the pump is "closed" when the pump shuts down. Meaning, the "shut after time delay" simulates a power failure to the pump impeller, which eventually may drop to zero rpm. However, flow can still pass through the zero-speed pump, unless you model a valve closure. Variable Speed/Torque pump shut down Another option to model a pump shutdown transient event is to use the variable speed/torque option. This could be used as part of a shutdown followed by startup . Or, it could be used to model a controlled shutdown, where the speed is ramped down. Here are the steps: 1) Set the pump Status(Initial) to 'On' 2) Set the Pump Type to "Variable Speed/Torque". 3) In the Time (Valve to Operate) property you enter the time to close the check valve or to open it if initial flow is zero. If the check valve allows flow only in one direction enter 0 (i.e. the pump has a built in check valve). To simulate a pump with no check valve or control valve enter a very large number like 9999 seconds so it never closes. If you enter a very small number like 0.1 seconds, the valve would close immediately after the start of the simulation, which would cause a transient response similar to a valve closure. 4) For the control variable properties you can choose either speed or torque. For more information on the difference between the variable speed and torque setting please refer to this wiki article . Here the default value is to control the speed of the impeller by using the pattern. If you want to control the pump using the torque control variable (so the momentum of the impeller is accounted for like with the shut down after time delay type) you have the option to do that too. For that approach, you will need to enter the nominal torque of the pump before it shuts down. The nominal torque is then multiplied by the operating rule pattern multiplier that will result in the torque values the numerical solver uses. To simulate the same behavior as the "shut after time delay", you would have the multiplier in the pattern drop from 1.0 (full applied torque) to zero in one timestep, at the time that you want the shutdown to occur. For a controlled shutdown, you would control either the speed or the torque to gradually ramp down the pump, per the operating rule. 5) Define the operating rule the pump will shut down based on. Click the dropdown button in the entry box and choose to create a pattern. 6) Under the Operational (Transient, Pump) section, right click to create a new pattern and set the starting multiplier equal to 1.000. In the section of the window under that enter the "Time from Start" , which is the time the speed or torque starts to drop. In the multiplier column enter 0 for when the speed or torque is zero. If you have the pump shut down between time steps 5 and 10 seconds for example it will gradually shut down over that period. Modeling a pump startup followed by shutdown, or shutdown followed by startup The variable speed transient pump type would be used to model both a shutdown and startup in the same simulation. See more here: Modeling a pump startup and shutdown transient event in the same simulation A Note on Pump-Turbines HAMMER currently does not support modeling an emergency shutdown event for a pump-turbine element (as typically the wicket-gate characteristics are built in) and the turbine element currently cannot start with reverse flow/speed. A pump-turbine option will be considered for a future release via Enhancement # 1060393. As a workaround, y ou may want to try a sensitivity analysis with the valve characteristics, using a pump element plus TCV for the wicket gate. Try a range of configurations that you feel are within what would represent the characteristics of the wicket gate closure (discharge coefficient and valve characteristics curves). Compare the overall transient results for different configurations and if they do not vary significantly, then you may not need to bother trying to accurately model the pump-turbine wicket gates. See Also Modeling a pump start up transient event in Bentley HAMMER How does pump inertia effect the pump calculations during a transient simulation? Modeling a pump startup and shutdown transient event in the same simulation
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