Hi Craig, what are saying means to use larger diameter with less slope rather than keep smaller diameter with higher slope (which in the range we specifying) !! but that leads to sedimentation in the sewage. it is all about getting the design optimized (sizing and depth); then the engineer look if the depth is not accepted and find other solution (add lift station, use larger diameter, change the path ...etc). I hope Bentley consider this very soon since it is very important if you they need enhancing the updates. Regards........Mohamad.

Hi In section 'Wave propagation in a Liquid' (P. 580) there is a sample which is confusing for me. What is the difference between c and a? What is the effect of direction of flow velocity in a pipe on characteristic wave celerity (a)?

Hi Scott See example below (MH- MH-CSE-08-184 vs MH-1242 ) of the same model. MH-CSE-08-184 0.0138+0.0173 = 0.031 Here SewerGEMS adds the fixed loads and puts it into the Dry weather flow of SWMM MH-1242 Here SewerGEMS exports the fixed load as a time series. This is inconsistent. I would prefer it for Sewergemes to only export it as a timeseries (this option) as all the loads would then be in the “Direct” inflows. Can you please advise give more clarity as to why this happens so I can export it only as “Direct flows” Rossouw Boshoff | Engineer, Water and Environment SMEC South Africa T +27 (31) 277 6702

If you are concerned with sedimentation, I recommend increasing the minimum velocity and minimum slope in the design constraints alternative.

Product(s): Bentley WaterGEMS, WaterCAD, HAMMER, SewerGEMS, SewerCAD, StormCAD, CivilStorm Version(s): N\A Environment: N\A Area: N/A Subarea: N\A Overview Bentley Hydraulics and Hydrology CONNECT integrated products can associate hydraulic models with a CONNECT project. This process is done with the Assign Project to Hydraulic Model dialog. Note: You must be signed in using the CONNECTION client to associate a CONNECTED project with a hydraulic model. A project needs to be registered before a hydraulic model can be associated. Benefits of Assigning a Project to a Hydraulic Model By assigning a project to a Hydraulic Model, Bentley will track which documents you use and time spent on your project and provide detailed project reports. Other benefits include: Better project time accounting Project performance analytics Project based learning and recommendations To Access the Assign Project to Hydraulic Model Dialog Open the Bentley Hydraulics and Hydrology CONNECT Integrated product. Sign-in to the CONNECTION client if you aren't already. Open or create a new Hydraulic model. The Assign Project to Hydraulic Model dialog will appear. Note: This dialog can also be accessed by opening the Bentley Cloud Services menu and selecting Associate Project. To Associate a CONNECTED Project to a Hydraulic Model In the Associate Project to Hydraulic Model dialog, select the desired CONNECTED Project from the list. Click Assign. The project name will display on the status bar to the left of your CONNECT user icon. To Change the Associated CONNECTED Project A hydraulic model can only have one project assigned to it. Assigning a project to a hydraulic model, that is already assigned to another project, will disassociate the existing project and associate the new project. To Disassociate a CONNECTED Project From a Hydraulic Model Open the Hydraulics and Hydrology product. Sign-in to the CONNECTION client if you aren't already. Open the hydraulic model to disassociate from a project. Open the Bentley Cloud Services menu and selecting Disassociate Project. The project name will no longer display on the status bar. See Also Associate Project to Workset Original Author: Craig Calvin

Applies To Product(s): Bentley SewerGEMS, Bentley CivilStorm, Bentley StormCAD Version(s): 08.11.XX.XX Environment: N/A Area: Original Author: Mark Pachlhofer, Bentley Technical Support Group Problem What is the difference between the Hydraulic Grade (HG) and Energy Grade (EG) 'Structure Loss' calculation option when using the GVF Rational Solver? Which is correct to use? Solution If you choose the EG option for the structure loss mode the headloss across the structure is the EGL (In) - EGL (Out) and the HGL is then calculated based off the EGL. On the other hand if you choose the HG option the headloss across the structure is the HGL (In) - HGL (Out) and the EGL is then calculated based off the HGL. We offer the two options because some engineers prefer that the headloss corresponds to the change in depth across the structure, while others prefer the headloss correspond to the change in energy. Note that when you choose the HG as your option the EGL at any given point is computed by adding the velocity head to the hydraulic grade and because of this energy discontinuities may occur, such as when a pipe size decreases in the downstream direction or a pipe slope increases. If you choose the EG as your option you can see the opposite effect where there could be discontinuities in the HGL. Flow discontinuities can also be responsible for energy discontinuities, since a structure is analyzed based on a different system time than a pipe, a direct comparison of energy grades is not reasonable. For the HEC-22 2nd edition it's fine to use either the HG or the EG option, although technically speaking the EG option is more correct. This is because the head loss by definition is the energy loss. When using the HEC-22 3rd edition, however, an engineer should only use the EG option for a structure loss method because HEC-22 specifically states that only the EG should be used when computing structure loss. See Also Hydraulic grade discontinuity at steep pipes or across nodes What are the differences between the HEC-22 2nd edition and the HEC-22 3rd edition?

I am wondering the proper tank mixing models to use for the following mixing systems: Tide Flex Horizontal Tide Flex Vertical "completely mixed" gives the best results for water age, but I want this to be as real world as possible as it may point to inadequate controls and tanks not turning over properly and having water stagnant in the tank! Using FIFO, the tanks seem to increase in age exponentially over time, so I need to know if this is actually happening or if it's something off with how I am modeling it!

Applies To Product(s): Bentley HAMMER Version(s): 08.11.xx.xx Environment: N\A Area: Modeling Subarea: N\A Original Author: Jesse Dringoli, Bentley Technical Support Group Problem How can I change the vapor pressure limit based on fluid properties, for fluids other than water? How does this affect the transient simulation results? Solution The default of -1 bar is for water at 20 C. If you're using a fluid other than water, the vapor pressure limit can be changed according to the values in the Liquid Engineering Library. To do this, click on the Vapor Pressure field in the properties of the Transient calculation options, then click the ellipsis button (...) next to it. Expand the liquid library, select the appropriate liquid, then click the Select button. You will notice that the Vapor Pressure field will change accordingly. As for how this affects the transient simulation: when the pressure at any given point in the network drops below the vapor pressure limit set in the calculation options, a vapor pocket will form. So, if subatmospheric pressures are occurring in your system, selecting the right vapor pressure limit may be important for an accurate simulation. For example if your pressure drops to -1.01 bar and your liquid has a vapor pressure limit of -1.1 bar, then you will see a vapor pocket form with the default vapor pressure (-1.0), but will not see one form with your liquid's vapor pressure limit. This can certainly affect the minimum and maximum transient pressures, because vapor pockets can cause severe upsurge pressures when they collapse. If you need to add a new liquid to the Liquid library, go to Components > Engineering Libraries, expand Liquid Libraries, right click LiquidLibrary.xml, choose "add item" and fill in the fields. This will now be available to choose from. You can also edit the vapor pressure values of existing liquid library entries if you need to. Of course, you always have the option of simply manually entering the appropriate vapor pressure limit, but you should also select the liquid in the Steady State/EPS Solver calculation options, so that the Initial Conditions are calculated correctly according to that liquid.

Product(s): Bentley SewerGEMS, SewerCAD, StormCAD, CivilStorm Version(s): 08.11.05.113 Area: N/A Introduction CONNECT Integration Informational Prompt when Opening or Creating a Hydraulic Model Assign Project to Hydraulic Model Dialog Connect Integrated Status Bar and CONNECTION Client Sign In Dialog Bentley Cloud Services Menu Publish i-model to My Shared Files Easier Export to Excel FlexTable Improvements Element Auto zoom "Select in Drawing" for selected rows Create selection sets from selected rows Context Menu to quickly add or remove columns Open subset of rows through Right-click menu Freeze Column capability Sort arrow to indicate what is sorted and which direction Faster filter workflow with auto selection feature FlexTable text search Global Edit on selected cells Introduction The CONNECT Services edition of Bentley software is the overall name given to Bentley software that enables the user to use Bentley software across numerous environments including desktop, cloud, servers and mobile applications. SewerGEMS V8i will initially remain a desktop application but with CONNECT, opportunities to be used on other environments are being added. Work flows that have been used with previous editions will still work, but in conjunction with new capabilities. Starting a model with a CONNECT services product opens a CONNECTION client on the user's computer which enables the user to access services on other Bentley web and cloud servers. The CONNECTION client is the desktop application that enables the user to access various CONNECT edition features. The CONNECTION client runs in the background and does not require the user to regularly interact with it. Bentley Cloud Services refers to the environment fostered by the CONNECT edition, where users can collaborate on projects using the web and the cloud through the user's Personal Portal. You can now publish i-models and pdf files from within SewerGEMS V8i and access them on other devices or share them with others using Personal Share. The Personal Portal is the starting point for Bentley CONNECT features, as opposed to the modeling features in SewerGEMS V8i. CONNECT Integration Informational Prompt when Opening or Creating a Hydraulic Model The following informational dialog will appear if you are signed in to the CONNECTION client when opening or creating a hydraulic model that does not already have an associated CONNECTED project. To prevent this dialog from appearing in the future: Check "Do not prompt again" and click OK. To enable the prompt again: Open the Tools menu and select options. In the Global tab, click the Prompts button. Then, uncheck "CONNECTED Project Notification" and click OK. Assign Project to Hydraulic Model Dialog The Assign Project to Hydraulic Model dialog can be used to register a new project, search for existing projects, and assign a project to a hydraulic model. Note: This dialog will appear if you are signed in to the CONNECTION client when opening or creating a hydraulic model that does not already have an associated CONNECT project. Register a Project: Opens the Register a Project page in your browser. Alternately, you can visit connect.bentley.com and select +New on the Recent Projects tile on your personal dashboard. Note: Only users with Admin/Co-admin roles can register a project. Refresh: Updates the list of projects. This may be necessary after creating a new project. View: Filters the project list to display projects added to your favorites, projects recently accessed, or it can be set to display all projects. Search: Finds projects by entering project information (number, name, location, industry, or asset type). Note: Do not use the asterisk wildcard * when searching. See the articles Associate Project to a Hydraulic Model and Register a Project for more information. Connect Integrated Status Bar and CONNECTION Client Sign In Dialog The CONNECTION client is installed with the CONNECT Integrated version of the Hydraulics and Hydrology product. When opening the CONNECT integrated version there will either be a user icon or it will display "Sign in". Clicking "Sign in" will display the CONNECTION Client sign-in dialog. From here, you can click the Register link to quickly create a profile, or sign in with your existing account information. Once you're signed in to the CONNECTION client you will see the user icon on the status bar. Clicking on the user icon will give options to go to your Personal Portal or to sign out. Once a project has been assigned to a hydraulic model, the project name (or a truncated version) will appear to the left of the user icon on the status bar. Clicking on the project name in the status bar will open the Project Portal . Bentley Cloud Services Menu The new Bentley Cloud Services menu provides quick access to your Personal and Project Portals. There are also options to associate or disassociate a CONNECTED Project with your file. The "Disassociate Project" and "Project Portal" options are only available if a project is associated with the hydraulic model. All options will be greyed-out if you are not signed in to the CONNECTION client. Publish i-model to My Shared Files You can now publish a hydraulic model's .imodel to a personal share on your Personal Portal . To do this: Go to File > Export > Publish Map Mobile i-model… Check "Publish .imodel to Personal Store" Specify export settings and click OK To access the personal share: Option 1: Click the user icon on the status bar and select Personal Portal. Option 2: Open the Bentley Cloud Services menu and select Personal Portal Option 3: Go to connect.bentley.com and sign in. You can view i-models with Bentley View (Free) , Bentley Navigator , and MicroStation . FlexTable Improvements Several usability improvements have been added to FlexTables: Element Auto zoom Selecting a FlexTable row header and pressing enter will zoom to that element. Note: This feature has also been added to the Alternative grids. Freeze, Select, Add, Remove Columns The FlexTables have some very useful new features added. By right clicking on the grey column headers you will see the Freeze Column, Select Column, Add Column, and Remove Column options. Freeze Column – Will freeze that column and all columns to the left of it, so when you have a lot of columns in your FlexTable and need to scroll to the right you can freeze columns. For example, this is come be useful to keep a column like the label constantly visible for identification purposes as you access other columns. Select Column – Allows you to easily select all the records in that column, which is useful if you want to copy the data from that row to spreadsheet. Add Column and Remove Column – In previous versions in order to add or remove a columns, you’d need to click the edit button at the top of the FlexTable, but now you can easily select a property to add to your FlexTable through the add column option. When you move your mouse cursor over the add option a popup menu appears that breaks all the columns down by their category (general, physical, results, geometry, etc…). This makes finding properties much simpler than choosing from the entire alphabetized listed using the edit button in previous version. If you still prefer the using the edit button to add and remove your columns you will still have that option. Element selection by highlighting rows Another feature that adds great flexibility is the ability to select rows in the FlexTable by clicking on them. Rows are selected the same way you select them in an Excel spreadsheet. Once selected you can right click on the row header and choose “Open on Selection”. This will filter your FlexTable by the rows you’ve choose. This will allow you to perform tasks such as creating a selection set or adding to a selection set with more ease. It will also allow you to select the elements in the drawing that you have selected in the FlexTables. In previous versions both of these tasks would have to be done in the drawing pane or by using queries. The screen shots below show the process of filtering a FlexTable on row selection and show the menus for making selection sets and selecting elements in the drawing. While the FlexTable is filtered you now also have the option to right click and global edit on a column for only the features in that selection set. Note: This feature has also been added to the Alternative grids. Sort arrow In the screen shot below you’ll see a small arrow has been added to columns that are sorted to indicated whether the sort is in ascending or descending order. Faster filter work workflow with auto selection When your right click on a column and choose to filter it using a custom query that column will now automatically be selected in the query builder to allow for faster queries to be created. In the screen shot below if you right-clicked on the diameter field outlined in blue and choose to filter by a custom query the diameter field in red would be automatically selected when the query builder opened. Find text in the FlexTable for faster feature location and selection Click the binoculars icon It will open this dialog that allow you to enter text to search the FlexTable Export to Excel Previously, data could be exported to Excel via the FlexTables, but needed to be done one by one and did not include time series. Now, there is an ability to export data for all element types at once, including time series (results over time). Steps: Go to, File > Export > Export to Excel. Then, in the Export to Excel dialog, specify properties and elements to be exported. Click OK. Note: these settings will be saved for the next export. In the FlexTable Export dialog, select either Excel or CSV format and specify where it will be exported. Click OK See Also Associate a Project to a Hydraulic Model User Registration Register a Project Bentley Cloud Services Overview CONNECTION client Options Sign In Using the CONNECTION client Project Portal Personal Portal Enterprise Portal SewerGEMS Help "CONNECT Services in SewerGEMS V8i" Original Author: Craig Calvin

Product(s): Bentley WaterGEMS Version(s): 08.11.03.17 Environment: N\A Area: Output and Reporting Subarea: N\A Problem The labels created in Element Symbology are not displayed on the drawing correctly. Is there a way to fix this? Product: WaterGEMS V8i Version: 08.11.03.17 Area: Output/Results Presentation, Problem ID#: 70821, PROBLEMSOLVING See Also: WaterCAD, StormCAD, SewerCAD, SewerGEMS, CivilStorm, PondPack, HAMMER Solution First, try to refresh the drawing by going to View > Refresh Drawing. If this doesn't work, synchronize the drawing with information in the database by going to Tools > Database Utilities > Synchronize Drawing. If the labels still do no appear, try changing the Drawing Style in Element Symbology. In large models, labels set to CAD style will be very small. If you change the drawing style to GIS, the labels may appear. You can also try refreshing the element symbology manager window in the standalone version of the software using the following icon in the screen shot below: See Also

Product(s): Bentley WaterGEMS, WaterCAD, HAMMER Version(s): 08.11.06.113 Area: N/A Introduction CONNECT Integration Informational Prompt when Opening or Creating a Hydraulic Model Assign Project to Hydraulic Model Dialog Connect Integrated Status Bar and CONNECTION Client Sign In Dialog Bentley Cloud Services Menu Publish i-model to My Shared Files Introduction The CONNECT Services edition of Bentley software is the overall name given to Bentley software that enables the user to use Bentley software across numerous environments including desktop, cloud, servers and mobile applications. WaterGEMS V8i will initially remain a desktop application but with CONNECT, opportunities to be used on other environments are being added. Work flows that have been used with previous editions will still work, but in conjunction with new capabilities. Starting a model with a CONNECT services product opens a CONNECTION client on the user's computer which enables the user to access services on other Bentley web and cloud servers. The CONNECTION client is the desktop application that enables the user to access various CONNECT edition features. The CONNECTION client runs in the background and does not require the user to regularly interact with it. Bentley Cloud Services refers to the environment fostered by the CONNECT edition, where users can collaborate on projects using the web and the cloud through the user's Personal Portal. You can now publish i-models and pdf files from within WaterGEMS V8i and access them on other devices or share them with others using Personal Share. The Personal Portal is the starting point for Bentley CONNECT features, as opposed to the modeling features in WaterGEMS V8i. CONNECT Integration Informational Prompt when Opening or Creating a Hydraulic Model The following informational dialog will appear if you are signed in to the CONNECTION client when opening or creating a hydraulic model that does not already have an associated CONNECTED project. To prevent this dialog from appearing in the future: Check "Do not prompt again" and click OK. To enable the prompt again: Open the Tools menu and select options. In the Global tab, click the Prompts button. Then, uncheck "CONNECTED Project Notification" and click OK. Assign Project to Hydraulic Model Dialog The Assign Project to Hydraulic Model dialog can be used to register a new project, search for existing projects, and assign a project to a hydraulic model. Note: This dialog will appear if you are signed in to the CONNECTION client when opening or creating a hydraulic model that does not already have an associated CONNECT project. Register a Project: Opens the Register a Project page in your browser. Alternately, you can visit connect.bentley.com and select +New on the Recent Projects tile on your personal dashboard. Note: Only users with Admin/Co-admin roles can register a project. Refresh: Updates the list of projects. This may be necessary after creating a new project. View: Filters the project list to display projects added to your favorites, projects recently accessed, or it can be set to display all projects. Search: Finds projects by entering project information (number, name, location, industry, or asset type). Note: Do not use the asterisk wildcard * when searching. See the articles Associate Project to a Hydraulic Model and Register a Project for more information. Connect Integrated Status Bar and CONNECTION Client Sign In Dialog The CONNECTION client is installed with the CONNECT Integrated version of the Hydraulics and Hydrology product. When opening the CONNECT integrated version there will either be a user icon or it will display "Sign in". Clicking "Sign in" will display the CONNECTION Client sign-in dialog. From here, you can click the Register link to quickly create a profile, or sign in with your existing account information. Once you're signed in to the CONNECTION client you will see the user icon on the status bar. Clicking on the user icon will give options to go to your Personal Portal or to sign out. After a project has been assigned to a hydraulic model, the project name (or a truncated version) will appear to the left of the user icon on the status bar. Clicking on the project name in the status bar will open the Project Portal . Bentley Cloud Services Menu The new Bentley Cloud Services menu provides quick access to your Personal and Project Portals. There are also options to associate or disassociate a CONNECTED Project with your file. The "Disassociate Project" and "Project Portal" options are only available if a project is associated with the hydraulic model. All options will be greyed-out if you are not signed in to the CONNECTION client. Publish i-model to My Shared Files You can now publish a hydraulic model's .imodel to a personal share on your Personal Portal . To do this: Go to File > Export > Publish Map Mobile i-model… Check "Publish .imodel to Personal Store" Specify export settings and click OK To access the personal share: Option 1: Click the user icon on the status bar and select Personal Portal. Option 2: Open the Bentley Cloud Services menu and select Personal Portal Option 3: Go to connect.bentley.com and sign in. You can view i-models with Bentley View (Free) , Bentley Navigator , and MicroStation . See Also Associate a Project to a Hydraulic Model User Registration Register a Project Bentley Cloud Services Overview CONNECTION client Options Sign In Using the CONNECTION client Project Portal Personal Portal Enterprise Portal WaterGEMS Help "CONNECT Services in WaterGEMS V8i" Original Author: Craig Calvin

I have not heard of the first two you mentioned so I would be curious to know as well. I would think that shape and amount will dictate age more than anything. If you understand Unix systems, there is a free program called OpenFOAM that will allow you to model the tank to determine dead spots within a tank. That will probably be the best to determine your age issues.

Hi Mike, I'm not sure of another way to put an answer in other terms of what the book already says, but I'll do my best. At a given point in the pipe 'c' is speed of wave and is equal to the wave celerity termed 'a' plus the velocity of the moving liquid. In other words, 'c' is just the total of the velocity of the water + the velocity of the wave in the water relative to a given fixed point. I'm not sure of how to answer the second question, but maybe Tom, Jesse, or another user can help you with that one. Regards, Mark

Applies To Product(s): Bentley WaterCAD, Bentley WaterGEMS Version(s): V8 XM, V8i Environment: N/A Area: Output and Reporting Subarea: N/A Original Author: Jesse Dringoli, Bentley Technical Support Group Overview This Technote explains how to interpret and troubleshoot calculated results for an automated fire flow analysis in WaterCAD or WaterGEMS V8 XM or V8i. Before reading this Technote, it is recommended that the user complete the Fire flow Quick start lesson. This is located in the WaterCAD/WaterGEMS help, under Contents > Quick Start Lessons > Automated Fire Flow Analysis. Background Fire Flow analysis is a common tool used in WaterCAD and WaterGEMS to ensure enough protection is provided during fire emergencies. The user is able to enter constraints in order to determine how much fire flow is available at hydrants while adequate system pressure is maintained. Several tools available to aid in understanding fire flow results. With the release of WaterGEMS V8i SELECTseries 6, the SCADAConnect Simulator tool has a new option: Fire response. Fire Response enables you to place a fire demand (or other emergency flows) at a node for a period of time to determine its impact on pressure and flows and possibly test alternative ways of responding to the fire. Here is the technote on that. How Does Automated Fire Flow Work? Fire flows are computed at each node by iteratively assigning demands and computing system pressures. When you execute a fire flow analysis, WaterCAD\GEMS will: Calculate a steady-state simulation for all nodes designated as fire-flow nodes. At each node, it begins by running a Steady-State simulation using only non-fire demands, to ensure that the fire flow constraints (e.g., minimum residual pressure, minimum zone pressure) that have been set can be met without withdrawing any Fire Flow from any of the nodes. Evaluate the Fire Flow Upper Limit and Available Fire Flow at each of the fire-flow nodes. Assuming the fire flow constraints were met in the initial run, the program performs a series of steady-state runs in which flow is applied to each specified fire-flow node and results are evaluated against fire-flow constraints. Note that the fire flow for each individual node is evaluated using a separate analysis (i.e., needed fire flow is not applied simultaneously to all fire-flow nodes). The program performs a series of steady-state analyses in which the Fire Flow Upper Limit discharge is applied to each node in turn. If the fire flow constraints are met for the Fire Flow Upper Limit discharge, the node satisfies the fire flow constraints and no further analysis is required for that node. The program then performs a series of steady-state analyses in which it iteratively assigns lesser demands to nodes that do not meet Fire Flow Upper Limit constraint to determine the Avalable Fire Flow. The Available Fire Flow is the maximum fire flow that each node can supply without violating fire flow constraints. If the Available Fire Flow is greater than or equal to Needed Fire Flow, the node satisfies the fire flow contraints. If Available Fire Flow is less than Needed, it does not. Run a final Steady-State calculation that does not apply Fire Flow demands to any of the junctions. This provides a baseline of calculated results that can then be compared to the Fire Flow conditions, which can be determined by viewing the results presented on the Fire Flow tab of the individual junction editors, or in the Fire Flow Tabular Report. Interpreting the Fire Flow Alternative Configuration for an automated fire flow analysis is done under the Fire Flow alternative. This is found under Analysis > Alternatives > Fire flow. When computing a scenario, the fire flow alternative assigned to that scenario is used. At a minimum, you should specify values for the needed Fire Flow, Fire Flow Upper Limit, Apply Fire Flow By, Residual Pressure Lower Limit, Zone Pressure Lower Limit and Fire flow nodes selection set. Below is an explanation of each of the main fields found in this alternative (when double clicking on it): Note: If the above options need to be configured differently for each junction/hydrant, you can specify "local" fireflow constraints by clicking the "specify local fireflow constraints?" check box next to the junctions/hydrants in the list at the bottom of the fireflow alternative. If this box is not checked, that particular fireflow node will utilize the global constraints entered at the top of the fire flow alternative. Note: it is important to understand that for the minimum zone pressure constraint, the program checks pressures for all other nodes in the model that are assigned to the same zone as the fireflow node in question. The zone is an attribute of the node. Say for example there are two nodes in the fireflow selection set: J-1 and J-2. J-1 is assigned to Zone A and J-2 is assigned to Zone B. Fireflow nodes are checked independently during the analysis, so when J-1 is being computed, the program will check pressures at all other nodes that are also assigned to Zone A and compare against the minimum zone pressure constraint. Then, when the analysis moves on to J-2, it will be checking pressure at all nodes assigned to Zone B. So, the program isn't running a fireflow analysis on a particular zone - it considers pressures at nodes assigned to certain zones, based on the fireflow node it is currently analyzing. Configuring your model to run a fire flow analysis After you've configured your fire flow alternative, the next step is to assign that alternative to the scenario you would like to compute. First, go to Analysis > Calculation Options. If you have an existing calculation option set that you're using in other scenarios, click on it and click the "duplicate" button. If you'd like, you could also click the "new" button to create a new calculation option set. Provide a meaningful name for your new calculation option set and double click it to open the properties. In the properties, set the Calculation Type to Fire Flow. Next, go to Analysis > Scenarios. Create a new scenario by choosing New > base scenario, or right click an existing scenario and choose "child". Provide a name for the new scenario, such as "Automated Fire Flow Analysis". Double-click your fire flow scenario to open the properties. Select your fire flow alternative from the dropdown next to "Fire Flow" and select your fire flow calculation option from the dropdown next to "Steady state/EPS solver Calculation options". Make your fireflow scenario current by right clicking it's name in the scenario manager and choosing "make current" or by selecting it from the Scenario dropdown menu bar at the top of your WaterCAD/WaterGEMS window. At this point, the automated fireflow analysis can be computed by going to Analysis > Compute. To understand the process that WaterCAD/GEMS uses, please see the section further above, entitled "How does the automated fire flow routine work?". Interpreting Automated Fire Flow Results There are several ways you can view the results of your automated fire flow analysis. Below describes the most common. Using the Fire Flow Report Make sure that your Fire Flow Analysis scenario is the current scenario and that you've succesfully computed it. Click Report > Element Tables > Fire Flow Report. The Fire Flow report is essentially a custom flextable including only the relevant fire flow results for both junctions and hydrants. The fields seen here can be added to the junction and hydrant flextables, but it is generally more convenient to use and keep this separate fireflow flextable when reviewing results of an automated fire flow analysis. Note: if you look at the general results in other flextables, such as "pressure" in the junction table, you will be viewing the baseline steady state results for your model, without any fire flow demands present. It is recommended that you only look at the fireflow table, so as not to be confused. The first thing you will notice is a column titled "Satisfies Fire Flow Constraints?" This will be checked only if the particular fire flow node (designated by the "label" for each row in this report) can provide at least the needed fire flow, while satisfying the fire flow constraints - the pressure constraints and sometimes the velocity constraints, if applicable. Here is a description of some of the other fields (columns) available in the fire flow report: Note: if your table does not display one or more of the below fields, you can add it using the yellow "edit" button at the top of the flextable. Is Fire Flow Run Balanced? "If set to true then the fire flow analysis was able to solve". Specifies whether the fireflow run was balanced or not for the given node. Using the Fire Flow Results Browser The Fire Flow Results Browser will allow you to check results for others elements in your model, during individual fire flow runs. Normally, the only results available after a fire flow analysis are the residual pressures at each fireflow node and minimum zone/system pressures. If you'd like to see other results, such as pipe velocities, hydraulic grades, valve status, etc, during a specific fire flow test, you can use this tool. First, you'll need to make sure that you have set up your Fire Flow Alternative for this function before running the fire flow analysis: After you have set up your Auxiliary Output Settings and run the Fire Flow analysis, go to Analysis > Fire Flow Results Browser. Select a fire flow node from the list to see the results for its adjacent pipes, and for the elements included in the output selection set (defined in the fire flow alternative). With a fire flow node selected, you can then establish color coding, annotations or simply check auxiliary results using the elemenet properties or flextables. For example, if you wanted to see the status of Valve X when Hydrant Y was flowed, click Hydrant Y in the list and then open the properties of Valve X. Color Coding Fire Flow Results Another good way to review an automated fire flow analysis is to use color coding. For example, you can color code junctions and hydrant based on the values for total available fire flow, to see areas where the available fire flow is lacking. Another useful color coding could be one based on the "satisfies fire flow constraints?" attribute. For example, you could color code such that junctions with "false" for this attribute show up as red, with a larger size. This would be done by using the "color and size" option, in the color coding dialog. You can also use color coding with the fire flow results browser. For example, you could color code pipe velocities so that when you click fire flow nodes from the fire flow results browser list, the colors will update to show the velocity distribution when that particular node was flowed. Troubleshooting Fire flow results not available In some cases, you may notice that the results in your fire flow report show "N/A" after computing the model. Make sure your scenario is set up correctly. Ensure that the correct fire flow alternative is assigned to the scenario that you are computing and ensure that its calculation options have the calculation type set to "fire flow". If this is set to "hydraulics only", fire flow results will not be computed. Make sure the scenario computed succesfully. If any messages show up under your user notification (Analysis > User notifications) with a red circle next to them, it means that the calculation failed. You'll need to address these fatal errors first, before results will be available. "N/A" entries can also be caused by omission from the fireflow selection set. In your fire flow alternative, make sure that all the nodes you'd like to study are included in the selection set selected for "Fire flow nodes". The fireflow routine will only analyze and provide results for nodes in this selection set. If desired, a filter can be used in the fire flow report so that nodes not included in the fire flow nodes selection set are not displayed. Make sure that you are not trying to use the fire flow results browser, if you haven't set up your fire flow alternative to save auxiliary results. Doing so can cause results in the fire flow flextable to show "N/A". This can be fixed by clicking the "reset to standard steady state results" button at the top of the fire flow results browser. Understanding why a node cannot provide the desired fire flow In the fire flow report (flextable), you may notice that one or more fire flow nodes does not satisfy the fire flow constraints. Meaning, the total available fire flow is less than the needed fire flow or below what you expected. There are several reasons why this could occur. First, check the calculated residual pressure field. This is the pressure at the fire flow node, at the total available fire flow. So, if this is equal to the residual pressure constraint, it means that the residual pressure constraint would be violated if any more flow was passed, so the fire flow routine stopped. If the calculated residual pressure is less than the residual pressure constraint, it probably means that the residual pressure was below the constraint even with the base demands (with no additional fire flow added). In this case, you should check the pressures in the model with baseline demands - they should all be above the constraints entered in the fire flow alternative. Next, check the calculated minimum zone pressure field. This is the lowest pressure out of all nodes in the same zone as the fire flow node in question, at the total available fire flow. So, if this is equal than the minimum zone pressure constraint that you entered, it means that the fire flow constrainted would be violated if any more flow was passed. So, the fire flow calculation stopped and reported the total available fire flow such that this would not be violated. If the calculated minimum zone pressure shows as less than the constraint, it probably means that the pressure somewhere else in that zone was less than the constraint, even with only the base demands (with no additional fire flow added). You should check the pressures in the model with baseline demands - they should all be above the constraints entered in the fire flow alternative. To check which specific node had the lowest pressure in the zone, check the "Junction with minimum pressure (zone)" field. In many cases, this may be a node at the suction side of the pump or at some other location that you may not be concerned with. In this case, it is recommended that you assign a different zone to these nodes. For example, create a zone called "low" and use that. This way, it won't be in the same zone as any fire flow nodes and thus won't be considered (unless you're using the minimum system pressure constraint). If you elected to use the minimum system pressure constraint in your fire flow alternative, you'll also need to check the calculated minimum system pressure. This is identical to the zone pressure constraint (see above), except it checks pressure at ALL nodes in the model. You can also check the "Junction with minimum pressure (system)" field to see which node caused the fire flow routine to stop. If you elected to use the Velocity constraint in your fire flow alternative, you'll also need to check the "Velocity of maximum pipe" and "Pipe w/ Maximum Velocity" fields. If the velocity in any pipe inside the chosen "pipe set" selection set exceeds the constraint you entered, the fire flow routine will stop. So, similar to the pressure constraints, you may notice the "Velocity of maximum pipe" is equal to or less than the constraint, indicating the reason why no additional fire flow could be extracted. Lastly, in rare cases, the fire flow routine may stop at a certain Total Available fire flow due to an unbalanced model. Meaning, at certain flow rates, the steady state simulation may not be able to converge on a balanced hydraulic solution within the maximum number of trials. This can occur in large, complex models, with low or near-zero flows, and/or when other data input in the model is not correct. It causes the results to be invalid and the fire flow run to stop. If your available fire flow is less than the upper limit, yet all the constraints described above are not violated, chances are that this was caused by the network becoming unbalanced. To check, try running a manual fire flow analysis on that junction. For the manual run, just make sure the calculation type in your calculation options is set to “Hydraulics only” and that you have entered the value for the total needed fire flow as an additional, fixed demand on that junction. Run the analysis and check your user notifications for an unbalanced error. One solution to this is to increase the max trials value in the calculation options, but you should also consider investigating other causes, such as data entry errors. Note: be aware of the presence of local fire flow constraints. At the bottom of your fire flow alternative, you can set node-specific constraints, which override the global constraints set at the top. This could potentially cause confusion when viewing fire flow results. For example, the total available fire flow for a certain node may be less than what you believe the needed fire flow value is, but still showing as satisfying the fire flow constraints. If you had a local "needed fire flow" set to a lower value, this could be valid. So, make sure you include and check the "Fire flow (needed)", "Fire flow (upper limit)" "Pressure (residual lower limit)" and "Pressure (Zone lower limit)" fields in your fire flow report/flextable. Consider the following Fire Flow Flextable, with no minimum system pressure or maximum velocity constraints used: J-10 - This node passed the fire flow test, as indicated by the "Satisfies fire flow constraints?" check box. It reports a Total available fire flow of 2012.68gpm, which is above the total needed fire flow of 462.68. Although the needed fire flow is actually 450.00gpm, we have chosen to add fire flows to base demands, and there is a base demand of 12.68gpm on this node. The total available amount of 2012.68gpm accounts for this base demand as well. Meaning, the total demand on this particular node can be up to 2012.68gpm without violating any fire flow constraints. The reason is because at the upper limit (2012.68gpm), both the residual pressure and minimum zone pressure are 59.2psi, which is above the constraints. The fire flow analysis stopped at the upper limit value to prevent unrealistically high flows from being computed. J-169 - This node passed the fire flow test with a reported total available fire flow of 557.82gpm. This is above the needed fire flow but below the upper limit. The reason why the fire flow test stopped at this flow is because a higher flow rate would violate the zone pressure constraint. As you can see, the calculated minimum zone pressure (lower limit) is equal to the user-entered minimum zone pressure constraint of 20psi and the "junction w/ minimum pressure (zone)" shows J-170. This means that although the residual pressure at J-169 (24.3psi) is above the constraints, J-170 is in the same zone as J-169 and had the lowest pressure, 20psi. J-171 - This node passed the fire flow test with a reported total available fire flow of 489.28gpm. This is above the needed fire flow but below the upper limit. The reason why the fire flow test stopped at this flow is because a higher flow rate would violate the residual pressure constraint. Although the minimum zone pressure of 23.5psi is above the 20psi constraint, the residual pressure (calculated pressure at J-171) is equal to the residual pressure constraint of 15psi. At a higher flow rate than 489.28gpm, the residual pressure would drop below 15psi, which would violate the pressure constraint. So, the fire flow analysis reports the maximum flow available without violating the constraint. J-159 - This node failed the fire flow test, as indicated by the unchecked "Satisfies fire flow constraints?". This is because the total available fire flow is 327.06gpm, which is less than the total needed flow of 453.17gpm. The reason why this node can only supply 327.06gpm is because of the residual pressure constraint. As you can see, even though the minimum zone pressure (60.4psi) is well above the zone pressure constraint, the calculated residual pressure is equal to the residual pressure constraint. This means that the pressure constaint would be violated at a flow any higher than 327.06gpm. J-154 - This node failed the fire flow test, because the available fire flow of 289.24gpm is less than the needed fireflow of 455.39. The reason it can only supply this much flow is because of the minimum zone pressure constraint. As you can see, although the residual pressure (28.5psi) is above the constraint, the minimum zone pressure is equal to the constraint, with J-158 as the "junction w/ minimum pressure (zone)". This means that J-158, which is in the same zone as J-154, is preventing any additional flow from being extracted, without violating the minimum zone pressure constraint. J-1 - This node failed the fire flow test with a total available flow of zero. This means that even without any demand at all on J-1, the baseline pressures in the model fall below the constraints. This is indicated by the calculated residual pressure of -1.4psi. This means that with zero demand on this node, the pressure at J-1 is -1.4psi. Since this is well below the constraint of 20psi, the fireflow test fails and the available fire flow is reported as zero. This particular junction is located on the suction side of a pump station, so it probably should be excluded from the fire flow nodes selection set. Meaning, it is probably unnecessary to compute fire flow for this node. J-2 - This node also failed the fire flow test with a total available flow of zero. In this case, it is because the minimum zone pressure constraint was violated. This means that without any demand at all on this node, the pressure at J-1 is -1.4psi. J-1 is in the same zone as J-2 and as seen above, it is at the suction side of the pump. So, assigning a new zone to J-1 should resolve this problem, since it would no longer be considered during the check of zone pressure. J-3 - This node, along with other junctions below it, show "N/A" for all calculated fields. This is because these nodes are not included in the fire flow nodes selection set , set in the fire flow alternative. Fire flow results browser not working If you attempt to use the fire flow results browser tool, you may run into problems if it is not configured correctly. Symtoms could be: Nothing showed up in the list. Some results show "N/A" in the properties/flextables after clicking a fire flow node from the list. This is caused by improper configuration in the fire flow alternative. Open the fire flow alternative and check the "Auxiliary output Settings" section. If you'd like to be able to check auxiliary results for any fire flow node, regardless of whether it passed or failed the "needed fire flow", select "All nodes" for the "Fire flow auxiliary results type". Doing this will ensure that all nodes show up in the list. At this point, at a minimum, you will be able to see auxiliary results for pipes adjacent to the fire flow node that you select in the results brower. If you'd like to see results for more elements, you'll need to choose a selection set for the "Auxiliary output selection set". If you want to be able to see auxiliary results for all nodes, you can create a selection set of all nodes. To do this, close the fire flow alternative, go to Edit > Select All. Right click anywhere in the drawing pane, choose "create selection set" and give it a name, such as "ALL ELEMENTS". Then, select this in your fire flow alternative for the output selection set. Now, when you compute the fire flow simulation, you'll be able to check results for all elements in the model, for your fire flow nodes. Note: the more fire flow nodes available in the list and the more elements included in the output selection set, the longer the calculation will take to perform and the more disk space it's saved results will take up. See Also WaterGEMS V8 Automated Fire Flow FAQ Product TechNotes and FAQs Haestad Methods Product Tech Notes And FAQs WaterGEMS V8 Automated Fire Flow FAQ [[General WaterGEMS V8 FAQ|General WaterGEMS V8 FAQ]] WaterGEMS V8 Modeling FAQ Hydraulics and Hydrology Forum Whats new in WaterGMES SS6 SCADAConnect Simulator for WaterGEMS SS6 Simulating a Fire Response in SCADAConnect Simulator

Applies To Product(s): Bentley WaterGEMS, Bentley WaterCAD Version(s): 08.11.XX.XX Environment: N/A Area: Original Author: Sushma Choure, Bentley Technical Support Group Problem Can I design sprinkler system using WaterGEMS or WaterCAD? Background I am trying to model a fire fighting system wherein a network of sprinklers is to be used. How do I input nozzle details? Can I use WaterGEMS for this? Solution Lay out the sprinkler system just as you would any other pipe network. At the location of the sprinklers, insert junction nodes. Simulate the flowing sprinkler(s) by setting their emitter coefficient to a value of the discharge coefficient you can obtain from sprinkler manufacturers. Be careful with units. Focus on the highest, most remote sprinklers. If they work, then the others should work as well. Consult the fire codes for the flow required and the number of sprinklers that need to be flowing simultaneously. You should also include the head losses through the backflow preventer and meter (if metered). You can use a GPV to represent them. If you are planning sprinkler system for a single story building, then the layout can be to scale. However, with multi-story buildings, this can get messy with each floor on top of one another. In that case, it is best to use non-scaled schematic mapping of the system. See Also How can i model a backflow preventer?

Hi, We are using Bentley software i.e. Water Cad, Sewer Cad, Storm Cad for the respective wet utilities design. We need to analyse the clash detection between utilities, please suggest the tools or software along with steps if possible through which we can do this tasks. Regards, Ajay

If you need further help with the WaterCAD model, we'll need some additional information on what these "tide flex" tanks look like, how the pipes connect, and a copy of the model file. There are two options for sharing your model on Communities. Either way, be sure to zip your files first. The first option is to attach to your reply on the forum using the Advanced Reply Editor (see link below and to the right of the reply box). If your data is confidential, use the instructions in the link below to send it via Bentley Sharefile. Files uploaded to Sharefile can only be viewed by Bentley. communities.bentley.com/.../7079.be-communities-secure-file-upload

The velocity of the flow doesn't effect the wave celerity, but it does effect how quickly a 'disturbance' moves along the pipeline. So if the flow velocity is +5 m/s and the wave celerity is 1000 m/s, then a 'disturbance' will move at 1005 m/s along the pipeline. If the flow velocity is reversed so that it is -5 m/s, then a 'disturbance' will move at 995 m/s along the pipeline. BUT, since flow velocities are typically several orders of magnitude less than wave celerities in water distribution systems, the flow velocity doesn't make much difference in practical terms. Regards, Mal

Hello Rohit, I have moved your post to the correct forum - Hydraulics and Hydrology Forum .

Hello Rohit, I have moved your post to the correct forum - Hydraulics and Hydrology Forum .