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Showing posts with the label Inside SWMM5

Use Sublime Text to Diff two files in the same folder for SWMM 5 C Code

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Sublime Text is nice but not a free Text Editor for large files.  However, it does have a limited file difference capability – here is how you can use Sublime Text to Diff two files in the same folder for SWMM 5 C Code.  You can also use this to compare dozens of files in Sublime - which is needed for a program such as SWM 5 which has been continuously updated from 2003 to 2017 with at least 35? major version.  This makes it easy for example to compare the groundwater or rdii code between 2005 / 2012 and 2017, for example.

Hydraulic Jump and Froude # in #SWMM5

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In this blog we example the Froude Number values computed in SWMM5 as equations, table, graphs and units. We use a QA/QC version of SWMM 5 that lists many more link, node, system and Subcatchment variables than the default SWMM 5 GUI and engine. This blog also applies to #InfoSWMM and any software the uses the #SWMM5 engine.  SWMM 5 computes only one flow in the middle of the link but it uses depth, head, cross sectional area and hydraulic radius at the upstream, midpoint and downstream points of the link (Figure 1).  The Froude # is computed at all three points and if you could see the Froude # you will see a jump at times in a single link (Figure 2).

RDII Components at a node for a 100 year simulation in SWMM 5

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Introduction:  This set of blogs uses the 1000 year rainfall/runoff/hydraulics model that you can download athttp://swmm2000.com/forum/topics/1000-year-simulation-with-rainfall-in-swmm-5 to show the inner workings of SWMM 5 and by extension InfoSWMM and H2oMap SWMM using a QA/QC version of SWMM 5 with extended graphics.   I always hope that seeing the inner workings of a SWMM 5 feature helps to understand the code, sensitivity and importance of a parameter.   It also helps show sometimes when a parameter is not important.   In this example, we show some of the internal working of the RDII estimation for SWMM5. 
Discussion:  There are nine main parameters for estimating RDII in SWMM 5: 1.Slow response or R1, T1 and K1
2.Medium response  R2, T2 and K2
3.Fast Response or R3, T3 and K3
4.The RDII flow is associated with a Node in SWMM 5 (Figure 1)
5.The RDII flow is composed of three separate time series generated from the slow, medium and fast R,  T and K values (Figure 2)
6.If you look…

The total losses include both evaporation and infiltration for a 100 Year SWMM 5 Simulation

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Introduction:  This set of blogs uses the 1000 year rainfall/runoff/hydraulics model that you can download athttp://swmm2000.com/forum/topics/1000-year-simulation-with-rainfall-in-swmm-5 to show the inner workings of SWMM 5 and by extension InfoSWMM and H2oMap SWMM using a QA/QC version of SWMM 5 with extended graphics.   I always hope that seeing the inner workings of a SWMM 5 feature helps to understand the code, sensitivity and importance of a parameter.   It also helps show sometimes when a parameter is not important.   In this example, the components of the total losses in SWMM 5 which are the infiltration from the pervious area and the evaporation from the impervious and pervious area are shown (Figure 1)
Discussion:The total losses (Figure 1) are: 1.The infiltration only losses from the pervious area,
2.Evaporation losses from the pervious and impervious area weighted by areal coverage
3.The total losses which are the sum of the evaporation plus infiltration losses
a.In a con…

Green Ampt Infiltration for the Storage Nodes of SWMM 5

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Introduction:  This set of blogs uses the 1000 year rainfall/runoff/hydraulics model that you can download athttp://swmm2000.com/forum/topics/1000-year-simulation-with-rainfall-in-swmm-5 to show the inner workings of SWMM 5 and by extension InfoSWMM and H2oMap SWMM using a QA/QC version of SWMM 5 with extended graphics.   I always hope that seeing the inner workings of a SWMM 5 feature helps to understand the code, sensitivity and importance of a parameter.   It also helps show sometimes when a parameter is not important.   Continuing with the recent blogs on Green Ampt Infiltration, you can also simulate the infiltration and evaporation from a Storage node in SWMM 5
Discussion:The infiltration and evaporation can be simulated in SWMM 5 using Green Ampt Infiltration: 1.The three Green Ampt parameters are entered in the Storage Node Dialog
2.The statistics for the whole run are shown in the Storage Node Summary Table for Volume, Percent Full and Percent Loss
3.The Node Storage Graph…

The Internal Green Ampt Parameters, Soil Moisture and IMD for a 100 Year SWMM 5 Simulation for Green Ampt Infiltration

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Introduction:  This set of blogs uses the 1000 year rainfall/runoff/hydraulics model that you can download athttp://swmm2000.com/forum/topics/1000-year-simulation-with-rainfall-in-swmm-5 to show the inner workings of SWMM 5 and by extension InfoSWMM and H2oMap SWMM using a QA/QC version of SWMM 5 with extended graphics.   I always hope that seeing the inner workings of a SWMM 5 feature helps to understand the code, sensitivity and importance of a parameter.   It also helps show sometimes when a parameter is not important.   In this example, we show some of the internal working of the Green Ampt Infiltration Parameters over the 100 year period. 
Discussion:  Key internal parameters for Green Ampt infiltration are
FUMax is the Saturated Moisture Content of the Upper Zone (internal units of feet) F or FTOT in the graph is the Cumulative event infiltration at start of time interval (internal units of feet) FU is the current moisture content of upper zone (internal units of feet)
As sh…

The Internal Green Ampt Parameters, FUMax, FU and FTOT or F for a 100 Year SWMM 5 Simulation for Green Ampt Infiltration

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Introduction:  This set of blogs uses the 1000 year rainfall/runoff/hydraulics model that you can download athttp://swmm2000.com/forum/topics/1000-year-simulation-with-rainfall-in-swmm-5 to show the inner workings of SWMM 5 and by extension InfoSWMM and H2oMap SWMM using a QA/QC version of SWMM 5 with extended graphics.   I always hope that seeing the inner workings of a SWMM 5 feature helps to understand the code, sensitivity and importance of a parameter.   It also helps show sometimes when a parameter is not important.   In this example, we show some of the internal working of the Green Ampt Infiltration Parameters over the 100 year period. 
Discussion:Key internal parameters for Green Ampt infiltration are
FUMax is the Saturated Moisture Content of the Upper Zone (internal units of feet) F or FTOT in the graph is the Cumulative event infiltration at start of time interval (internal units of feet) FU is the current moisture content of upper zone (internal units of feet)
As shown in Figu…

Initial Moisture Deficit or IMD for a 100 Year SWMM 5 Simulation for Green Ampt Infiltration

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Introduction:  This set of blogs uses the 1000 year rainfall/runoff/hydraulics model that you can download athttp://swmm2000.com/forum/topics/1000-year-simulation-with-rainfall-in-swmm-5 to show the inner workings of SWMM 5 and by extension InfoSWMM and H2oMap SWMM using a QA/QC version of SWMM 5 with extended graphics.   I always hope that seeing the inner workings of a SWMM 5 feature helps to understand the code, sensitivity and importance of a parameter.   It also helps show sometimes when a parameter is not important.   In this example, we show some of the internal working of the Green Ampt Infiltration Parameters over the 100 year period.  The IMD is normally near the initial user defined value but it can go to zero during the course of the simulation (Figure 1)
Discussion:  A key internal and user defined parameter is the Green Ampt Infiltration parameter Initial Moisture Deficit.  It starts out at the user Initial Deficit and then is computed at each hydrology time step…

Rainfall and Losses One Watershed for a 100 Year Simulation with SWMM 5 Statistics at a saved time step of one hour.

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Introduction:  This set of blogs uses the 1000 year rainfall/runoff/hydraulics model that you can download athttp://swmm2000.com/forum/topics/1000-year-simulation-with-rainfall-in-swmm-5 to show the inner workings of SWMM 5 and by extension InfoSWMM and H2oMap SWMM using a QA/QC version of SWMM 5 with extended graphics.   I always hope that seeing the inner workings of a SWMM 5 feature helps to understand the code, sensitivity and importance of a parameter.   It also helps show sometimes when a parameter is not important.   In this example, we show how the statistics change when you change the reporting time step.  You can only see what you report, if you only save every hour or 15 minutes then you may miss some important model results.
Discussion:  In this blog we look at the Rainfall and Pervious Losses for the 100 year period: Generally, it is better to have finer time steps for rainfall and for reporting.    As you can see in Figure 1 we only get pervious runoff when the ra…

Runoff from One Watershed for a 100 Year Simulation with SWMM 5 Statistics for the Subcatchment Impervious and Pervious Depth

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Introduction:  This set of blogs uses the 1000 year rainfall/runoff/hydraulics model that you can download athttp://swmm2000.com/forum/topics/1000-year-simulation-with-rainfall-in-swmm-5 to show the inner workings of SWMM 5 and by extension InfoSWMM and H2oMap SWMM using a QA/QC version of SWMM 5 with extended graphics.   I always hope that seeing the inner workings of a SWMM 5 feature helps to understand the code, sensitivity and importance of a parameter.   It also helps show sometimes when a parameter is not important.  
Discussion:  In this blog we look at the Subcatchment Runoff Depth for the three types of Subcatchment Surfaces in SWMM 5: 1.Impervious with depression storage
2.Impervious without depression storage
3.Pervious area with depression storage

As you can see in the graphs of depth (Figure 1) the pervious depth is often zero as the infiltration is greater than the continuous rainfall.  Of course this depends on the rainfall intensity, infiltration type and infiltrat…

Runoff from One Watershed for a 100 Year Simulation with SWMM 5 Statistics for Peak, Mean and Total Runoff

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Introduction:  This set of blogs uses the 1000 year rainfall/runoff/hydraulics model that you can download athttp://swmm2000.com/forum/topics/1000-year-simulation-with-rainfall-in-swmm-5 to show the inner workings of SWMM 5 and by extension InfoSWMM and H2oMap SWMM using a QA/QC version of SWMM 5 with extended graphics.   I always hope that seeing the inner workings of a SWMM 5 feature helps to understand the code, sensitivity and importance of a parameter.   It also helps show sometimes when a parameter is not important.  
Discussion:  In this blog we look at the Runoff total over the 100 year period, graph the runoff (Figure 1) and show the Mean, Total and Peak Runoff using the Statistics Command in SWMM 5.   The Frequency plots shown in Figure 1 are made using event separation time of 6 hours.  The number of Runoff Events over the 100 year period is 11,144 events.   The details of the simulation are shown in Figure 2.

[TITLE]
[OPTIONS] FLOW_UNITS           CFS INFILTRATION     …

The Link Time Step in SWMM 5, InfoSWMM and H2OMap SWMM

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Introduction:  This set of blogs uses the 1000 year rainfall/runoff/hydraulics model that you can download athttp://swmm2000.com/forum/topics/1000-year-simulation-with-rainfall-in-swmm-5 to show the inner workings of SWMM 5 and by extension InfoSWMM and H2oMap SWMM using a QA/QC version of SWMM 5 with extended graphics.   I always hope that seeing the inner workings of a SWMM 5 feature helps to understand the code, sensitivity and importance of a parameter.   It also helps show sometimes when a parameter is not important.  

Discussion:  Here we look at the link time step for a 100 year simulation.   If you use the Variable Time Step in SWMM5 with the CFL Adjustment factor the program will compute the needed link time step at each simulation time step based on the last time steps depth, velocity and width.  The link time step is
Link Time Step = Adjustment Factor * CFL Explicit Time Step for the Controlling Link
The time step is larger for low flows and decreases as the flow in t…