SWMM5 - Stormwater Management Model
SWMM 5, InfoSWMM, H20MAP SWMM, InfoSewer for Water Quality,Hydrology, Hydraulics
Top Content
Latest Activity
Robert Dickinson commented on Robert Dickinson's group 'ExtraVariables'
QA/QC version based on v22 of EPA SWMM 5 with the ability to read older SWMM 5 OUT files.
swmm5.dll
Epaswmm5.exe
Robert Dickinson commented on Robert Dickinson's group 'Stream of Information'
Video: How Snowflakes Are Formed
February 4th, 2012 | Posted by Jaime Menchén in Science Videos
This time-lapse video lasts 11 seconds, with no music or voice-over. And still you’ll want to see it over and over again. The…
Photo posted by Robert Dickinson
This is a galaxy
This is a galaxy. Or is it? A remix of material originally produced for BBC Stargazing Live 2012 If you liked this video, follow me on twitter to hear about ...
Video posted by Robert Dickinson
Fateme Fallah replied to Fateme Fallah's discussion 'Uncertainty Analysis'
Dear Lionel,
This matter is explained in Appendix D of SWMM manual under the title of “Command line SWMM”. So in MATLAB you can use below format under DOS window:
"The address of place that SWMM is there" input…
Robert Dickinson commented on Robert Dickinson's group 'Stream of Information'
Now the new images, courtesy of the Suomi NPP satellite (2012):
The above two photos are pretty much what you would see with your naked eyes if you were at the altitude of this satellite. It's humbling to realize that all you…
Lionel replied to Lionel's discussion 'Linking Matlab with SWMM5'
Thanks Robert for your prompt help!
Lionel replied to Fateme Fallah's discussion 'Uncertainty Analysis'
Hi Fateme Fallah,
I am doing something similar but in my case I am varying the infiltration factor. I am not very good with Matlab so require a bit of help on the coding. I would like to check if you have been successful in your attempt to…
Robert Dickinson replied to Lionel's discussion 'Linking Matlab with SWMM5'
Hi, This thread has some info
http://www.swmm2000.com/forum/topics/uncertainty-analysis
as does this
http://www.swmm2000.com/forum/topics/link-swmm-with-matlab
http://www.swmm2000.com/forum/topics/combining-swmm-and-matlab
Linking Matlab with SWMM5
Hi, I am currently trying to use Matlab to create a set of random values and inputting these random values into SWMM 5 to vary the different parameters (e.g. decay constant) so I will get a range of results. Has anyone done it before? Thanks!See More
Discussion posted by Lionel
North Carolina City Chooses InfoSewer
North Carolina City Chooses InfoSewerArcGIS Based Sewer Modeling Package Helps Hendersonville, NC Model and Manage Its Collection SystemBroomfield, Colorado, USA, January 31, 2012Innovyze, a leading global innovator of business analytics software and technologies for wet infrastructure, today announced the City of Hendersonville, North Carolina, has selected InfoSewer for ArcGIS (Esri, Redlands, CA) as its sewer modeling platform.InfoSewer has helped define the standard in the industry for…See More
A blog post by Robert Dickinson was featured
North Carolina City Chooses InfoSewer
North Carolina City Chooses InfoSewerArcGIS Based Sewer Modeling Package Helps Hendersonville, NC Model and Manage Its Collection SystemBroomfield, Colorado, USA, January 31, 2012Innovyze, a leading global innovator of business analytics software and technologies for wet infrastructure, today announced the City of Hendersonville, North Carolina, has selected InfoSewer for ArcGIS (Esri, Redlands, CA) as its sewer modeling platform.InfoSewer has helped define the standard in the industry for…See More
Blog post by Robert Dickinson
Robert Dickinson left a comment for oliver kemp
Welcome Oliver!
Automatic Weighting
Purpose: The purpose of this note is to explain a significant dynamic wave routing difference between EPA SWMM 5.0.013 and EPA SWMM 5.0.011 and before. A few people have detected a difference. The previous solution(s) would use only the midpoint area (Amid) and hydraulic radius (Rmid) in the dynamic wave solution. The new solution will use a slider or linear combination of the midpoint area (Amid) and hydraulic radius (Rmid) and the upstream cross sectional area (A1) and hydraulic radius (R1). The slider is based on the Froude number in the link. The change involves the A and R link spacing in the two dominant terms of the St. Venant Equation:
The new method is a linear combination or slider that weights the value of A and R in the St. Venant Equation based on the value of rho (
), or
where, Rho () is a function of the Froude number. The effect of this addition is that as the Froude number increases from 0.5 to 1.0 and beyond the area and hydraulic radius used as the pivot point in the St. Venant equation moves from the midpoint of the link to the upstream end of the link. When the Froude number is above 1.0 the St. Venant and Normal Flow equation both use the same cross sectional area and hydraulic radius which makes for a more stable model.
Just for reference, the equation for Qnorm or the Manning's Equation flow is
The equations for the calculation of Rho () as a function of the Froude Number (Fr) are:
If ALL of the follow conditions are true Rho ()is calculated:
where,
h1 is the head at the upstream end of the link,
h2 is the head at the downstream end of the link and
qLast is the last flow value in the link.
If any of these conditions are true then rho = 1.0 and the value of A and R are the values Amid and Rmid, respectively.
The next graph shows the relationship between Rho and the Froude Number.
The value of Awtd and Rwtd move from the midpoint of the link to the upstream end of the link as the Froude number increases from 0.5 to 1.0.
Conclusion: This change should make the solution more stable because there is no longer an oscillation between the St. Venant Equation A and R and the Normal Flow Equation A and R.
The new method is a linear combination or slider that weights the value of A and R in the St. Venant Equation based on the value of rho (
), or where, Rho (
) is a function of the Froude number. The effect of this addition is that as the Froude number increases from 0.5 to 1.0 and beyond the area and hydraulic radius used as the pivot point in the St. Venant equation moves from the midpoint of the link to the upstream end of the link. When the Froude number is above 1.0 the St. Venant and Normal Flow equation both use the same cross sectional area and hydraulic radius which makes for a more stable model.Just for reference, the equation for Qnorm or the Manning's Equation flow is
The equations for the calculation of Rho (
) as a function of the Froude Number (Fr) are: If ALL of the follow conditions are true Rho (
)is calculated:- the pipe is not full,
- h1 >= h2, and
- qLast > 0.
where,
h1 is the head at the upstream end of the link,
h2 is the head at the downstream end of the link and
qLast is the last flow value in the link.
If any of these conditions are true then rho = 1.0 and the value of A and R are the values Amid and Rmid, respectively.
The next graph shows the relationship between Rho and the Froude Number.
The value of Awtd and Rwtd move from the midpoint of the link to the upstream end of the link as the Froude number increases from 0.5 to 1.0.
Conclusion: This change should make the solution more stable because there is no longer an oscillation between the St. Venant Equation A and R and the Normal Flow Equation A and R.
Last updated by Robert Dickinson Jun 7, 2008.
© 2012 Created by Robert Dickinson.
Powered by 
.
