SewerCAD has the ability to analyze time-based or extended period simulations (EPS). This lesson illustrates different aspects of setting-up and running an EPS including:
• Developing loading patterns and hydrographs • Calculating the model
• Viewing time-based output
For this lesson, we will use the system designed in Lesson 4. If you did not complete Lesson 4, you may also use the file lesson5.swr, or lesson5.dwg in AutoCAD. This file is located in the SWRC / Lessons directory. After opening the file, select the "Design Trial #2" scenario from the Scenario toolbar.
If, at any time during this lesson, the program asks, "Do you wish to reset all calculated results to N/A?" click NO.
Part 1 - Entering and Applying Loading Patterns
Loading patterns are a series of time-based multipliers that are applied to average loads, which describe how the load varies over time. In this lesson, we are going to create a loading pattern and apply it to the unit sanitary loads established with the model in an earlier lesson, and to a new Pattern Load.
To create a new loading pattern select Analysis / Patterns from the pull-down menus. Click the Add button to bring up a new Pattern dialog.
Enter "Lesson 5 Pattern" in the Label field. Then enter 0 as Start Time, and Starting Multiplier of 0.4. Then fill in the pattern table on the right-hand side of the dialog starting at hour 3.
Loading Pattern Data
Time (hours) Multiplier 0 0.4 3 0.8 6 1.2 9 1.7 12 1.4 15 1.2 18 1.3 21 0.6 24 0.4
Notice that the starting and final multipliers at hour 0 and 24 are equal. The program requires this so in the case you run the simulation longer than 24 hours then the pattern can repeat itself.
Make sure that the format of the pattern is set to Continuous. You can see a graph of the loading pattern by clicking the Report button and selecting Graph.
To apply this pattern to the various used unit dry weather labels, select Analysis / Pattern Setups from the pull-down menus. The Pattern Setup Manager works in a similar manner to the Extreme Flow Setup Manger, as described in Lesson 1. In this case different patterns are applied to unit sanitary loads as opposed to extreme flow methods. As with extreme flow setups, you can create different pattern setups and associate them with different scenarios.
Click the Add button to create a new pattern setup. In the Label field enter in "Lesson 5."
In this lesson, for the sake of simplicity, we will apply the same pattern to all the unit loads. To do so, right click on the Diurnal Pattern column heading and select Global Edit. Select Lesson 5 Pattern from the drop-down menu and click OK.
Click OK to exit back to the Pattern Setup Manager. Click OK to exit back to the drawing.
You can also apply loading patterns to base loads set at individual hydraulic elements. To do so, enter the editor for MH-1, and click the Loading tab. Click the Add button next to the Sanitary (Dry-Weather) Flow pane. In the Load Definition pull-down menu select Pattern Load - Base Flow & Pattern, and click OK.
Enter in a Base Load of 2000 l/d, and select Fixed from the Pattern pull-down menu. Click OK to go back to the manhole editor, and then click OK in the editor dialog.
Part 2 - Entering Hydrographs
SewerCAD also allows you to enter in hydrographs as a sanitary load (at manholes, wet wells, and pressure junctions), or as inflows and infiltration (at manholes, pressure junctions, wet wells and gravity pipes). To explain the concept, we will enter in a single hydrograph as a wet-weather load at manhole MH-2. Enter the manhole editor for manhole MH-2, and click the Loading tab. Click the Add button next to the Inflow pane.
Select Hydrograph - Flow vs. Time from the Load Definition pull-down menu, and click OK. Enter "MH-2 Hydrograph" in the Label field. Then fill in the hydrograph with the data in the following table.
Hydrograph Data Time (hours) Discharge (l/d) 0 0 3 2500 6 4800 9 7300 12 19500 15 7300 18 4900 21 2400 24 0
Click OK to close the Hydrograph dialog, and click OK again to go back to the drawing pane.
Part 3 - Running the Analysis
To run the EPS, click the GO button. In the Scenario dialog change the Calculation Type from Steady State to Extended Period. Leave the Duration, Hydraulic Time Step, Hydrologic Time Step set to 24, 1.00, and 0.1 respectively. Change the Pattern Setup from the Base Pattern Setup to Lesson 5.
Click the GO button in the dialog. The program will then calculate output, and when the results appear click the Close button.
Part 4 - Time Based Graphs and Tables
In SewerCAD you have the capability of creating time based graphs and tables for the comparison of hydrographs at multiple elements within the system.
Say we would like to compare the hydrographs generated at manholes, MH-1 and MH-2, and see the combination of the two routed hydrographs as they exits JC-1. To do so, select Report / Hydrograph Reports.
Under the Scenarios tab make sure "Design Trial #2" is checked. If multiple scenarios are checked you will see the hydrograph generated for each of the scenarios for the same element. In this case, only check the one scenario.
Click the Elements tab. If any elements are selected in the drawing pane they will already selected. Make sure that the three selected elements are: MH-1, MH-2 and JC-1.
When those elements are selected click the OK button to see the plot.
You can also see this information in a tabular format by clicking the Data tab. This will bring up the table. By clicking the Copy button the information will be copied to the clipboard you will be able to paste it into other Windows Applications such Microsoft Word or Excel.
Click Close to exit the plot back to the drawing pane.
You can also create other comparison graphs of attributes over time other than flow by selecting Report / Element Graph from the pull-down menus and then selecting the element type for which to generate a plot. As an example, select Manhole.
Under the Graph Setup tab select Hydraulic Grade Line Out as the Dependent Variable. Then select MH-1 and MH-2 under the Elements tab. Make sure that "Design Trial #2" is selected under the Scenarios tab. Click OK to view the graph. As you can see, the format and functionality is same as has the hydrograph plot viewed earlier. Click Close to return to the drawing pane.
Part 5 - Animations
SewerCAD’s animation tool is a dramatic, effective way of presenting and analyzing output data. In this example, we will animate the color-coding on the main drawing pane, and the hydraulic grade line on the profile plot.
Before we animate the drawing pane, we need to color code by attribute that varies with time. In this case color code the links based on Total Flow attribute. Use the same procedure described in Lesson 4. To animate the drawing pane simply click the VCR-style play button in the Analysis Toolbar. To stop the animation click the stop button which appeared upon clicking play.
If you wish to change the frame rate - click the down arrow next to the play button, and select Animation Delay. Increase or decrease the value depending on your preferences. Click OK to exit the dialog. Profiles can also be animated in the same manner as the drawing pane. Reopen the profile created in Lesson 4, from MH-2 to the WW-1. Select Tools / Profiling from the pull-down menus. Select the MH-2 to WW-1 profile and click Open. Simply click the play button in the profile window to start the animation and click it again to stop it.
From these five lessons, you have had a brief introduction to the capabilities of SewerCAD. Feel free to continue to play with the program. Use this model to explore and become familiar with all of the features. If you do not know what a button does, just try it.
Chapter 4
Starting a SewerCAD Project
4.1 Overview
This chapter describes how to start a new project and the files that SewerCAD creates to save your project’s data. At the beginning of a project, you also need to set some global settings (accessed from the Tools / Options pull-down menu).