SWMM-USERS Digest - 14 Dec 2009 to 15 Dec 2009 (#2009-137)
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There are 4 messages totalling 1532 lines in this issue.
Topics of the day:
1. Modeling Forcemains in SWMM5 (4)
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Date: Tue, 15 Dec 2009 02:12:11 -0700
From: Robert Dickinson <Robert.E....@US.MWHGLOBAL.COM>
Subject: Re: Modeling Forcemains in SWMM5
Hi Jason,
There is a great table in the SWMM 5 output file, the Node Inflow Summary, =
that will show you both the lateral flow into a node and the total inflow a=
t the node. You can use this table to check the mass balance between any t=
wo nodes of your network. If you check the total inflow at the upstream no=
de of your pump and the downstream node of your forcemain you should see a =
good balance if you make the following adjustments:
1. If you are simulating pumps that turn on very frequently you should try=
using a 5 second time step or less,
2. I would suggest using a hotstart file to both lower any potential conti=
nuity error and warm up your network faster,
3. It would be better to use BOTH as an option for normal flow as this wil=
l trigger the normal flow equation for both water surface slope less than t=
he bed slope and a Froude number > 1 at either end of your links,
4. If you use KEEP as the inertial term option it will use all of the term=
s in the St. Venant equation for partial flow, if the force main is full th=
e non-linear term will drop out anyway as both end of the link have the sam=
e cross sectional area in this situation.
5. I would also suggest that you use the variable time step option just in=
case the program needs to lower the routing time step sometime during the =
simulation.
6. The total inflow of 0.173 at your loading node and the total node inflo=
w of 0.175 at the downstream end of the force main is very close especially=
based on the number of times your pumps turn on during the course of the s=
imulation.
*******************
Node Inflow Summary
*******************
-----------------------------------------------------------------------=
--------------
Maximum Maximum Lateral=
Total
Lateral Total Time of Max Inflow=
Inflow
Inflow Inflow Occurrence Volume=
Volume
Node Type LPS LPS days hr:min 10^6 ltr=
10^6 ltr
-------------------------------------------------------------------------=
------------
Best and Kind Regards,
Robert E Dickinson
Technical Engineering Specialist
MWH Soft, Inc
9340 Pontiac Drive Tel: 813-712-0664
Tampa, Florida, 33626 Alt: 813-494-2919
USA
robert.d...@mwhsoft.com
www.mwhsoft.com
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of Brin=
k, Philip
Sent: Monday, December 14, 2009 11:53 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Good; I would assume you would have already checked that, but sometimes
it's the simple or what should be obvious that can cause a perplexity. I
will also assume you have a fine-enough reporting interval so you aren't
missing any instability or peak flows that might be passing through as
well (but that'd be my next thought). You may want to post the file for
further input.
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 2:40 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
No. There is only the flow at the one node upstream of the pump station.
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Brink, Philip
Sent: December-14-09 11:34 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Do you possibly have some baseflow assigned at the pump station or at
the node(s) downstream?
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 1:30 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: [SWMM-USERS] Modeling Forcemains in SWMM5
I have constructed two hydraulic models for sanitary sewer systems and
am receiving the same odd results in both.
The cumulative net inflow into the pump station totals to a sum "x".
The cumulative net inflow at the downstream node of the forcemain is the
same value "x".
However, in the next node downstream from the forcemain, the net inflow
into the node is greater than "x".
There is only one source of flow in all of the network which is upstream
of the pump station.
What could be causing this mysterious "additional flow"?
I will not be able to predict residual capacity in the system with any
confidence unless this is resolved.
Thanks and have a great holiday season.
Disclaimer :
The information transmitted is intended only for the person or entity to
which it is addressed and may contain confidential and/or privileged
material. Any review, transmission, dissemination or other use of, or
taking of any action in reliance upon, this information by persons or
entities other than the intended recipient is prohibited. If you
received this in error, please contact the sender and delete the
material from any computers.
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The information transmitted is intended only for the person or entity to
which it is addressed and may contain confidential and/or privileged
material. Any review, transmission, dissemination or other use of, or
taking of any action in reliance upon, this information by persons or
entities other than the intended recipient is prohibited. If you
received this in error, please contact the sender and delete the
material from any computers.
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------------------------------
Date: Tue, 15 Dec 2009 09:16:17 -0400
From: "Wilson, Alexander" <alexa...@CBCL.CA>
Subject: Re: Modeling Forcemains in SWMM5
Hi Jason,
To add my 2 cents to Bob's list, I had a similar experience, which was
resolved by removing
the conduit lengthening option (changed it to 0). It was artificially
creating volume in the system.
Alexander.
Alexander T. Wilson, M.Eng, P.Eng.
Water Resources Engineer
CBCL Limited, Consulting Engineers
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Robert Dickinson
Sent: Tuesday, December 15, 2009 5:12 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Hi Jason,
There is a great table in the SWMM 5 output file, the Node Inflow
Summary, that will show you both the lateral flow into a node and the
total inflow at the node. You can use this table to check the mass
balance between any two nodes of your network. If you check the total
inflow at the upstream node of your pump and the downstream node of your
forcemain you should see a good balance if you make the following
adjustments:
1. If you are simulating pumps that turn on very frequently you should
try using a 5 second time step or less,
2. I would suggest using a hotstart file to both lower any potential
continuity error and warm up your network faster,
3. It would be better to use BOTH as an option for normal flow as this
will trigger the normal flow equation for both water surface slope less
than the bed slope and a Froude number > 1 at either end of your links,
4. If you use KEEP as the inertial term option it will use all of the
terms in the St. Venant equation for partial flow, if the force main is
full the non-linear term will drop out anyway as both end of the link
have the same cross sectional area in this situation.
5. I would also suggest that you use the variable time step option just
in case the program needs to lower the routing time step sometime during
the simulation.
6. The total inflow of 0.173 at your loading node and the total node
inflow of 0.175 at the downstream end of the force main is very close
especially based on the number of times your pumps turn on during the
course of the simulation.
*******************
Node Inflow Summary
*******************
------------------------------------------------------------------------
-------------
Maximum Maximum
Lateral Total
Lateral Total Time of Max
Inflow Inflow
Inflow Inflow Occurrence
Volume Volume
Node Type LPS LPS days hr:min 10^6
ltr 10^6 ltr
------------------------------------------------------------------------
-------------
Best and Kind Regards,
Robert E Dickinson
Technical Engineering Specialist
MWH Soft, Inc
9340 Pontiac Drive Tel: 813-712-0664
Tampa, Florida, 33626 Alt: 813-494-2919
USA
robert.d...@mwhsoft.com
www.mwhsoft.com
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Brink, Philip
Sent: Monday, December 14, 2009 11:53 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Good; I would assume you would have already checked that, but sometimes
it's the simple or what should be obvious that can cause a perplexity. I
will also assume you have a fine-enough reporting interval so you aren't
missing any instability or peak flows that might be passing through as
well (but that'd be my next thought). You may want to post the file for
further input.
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 2:40 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
No. There is only the flow at the one node upstream of the pump station.
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Brink, Philip
Sent: December-14-09 11:34 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Do you possibly have some baseflow assigned at the pump station or at
the node(s) downstream?
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 1:30 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: [SWMM-USERS] Modeling Forcemains in SWMM5
I have constructed two hydraulic models for sanitary sewer systems and
am receiving the same odd results in both.
The cumulative net inflow into the pump station totals to a sum "x".
The cumulative net inflow at the downstream node of the forcemain is the
same value "x".
However, in the next node downstream from the forcemain, the net inflow
into the node is greater than "x".
There is only one source of flow in all of the network which is upstream
of the pump station.
What could be causing this mysterious "additional flow"?
I will not be able to predict residual capacity in the system with any
confidence unless this is resolved.
Thanks and have a great holiday season.
Disclaimer :
The information transmitted is intended only for the person or entity to
which it is addressed and may contain confidential and/or privileged
material. Any review, transmission, dissemination or other use of, or
taking of any action in reliance upon, this information by persons or
entities other than the intended recipient is prohibited. If you
received this in error, please contact the sender and delete the
material from any computers.
**********************************************************
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The information transmitted is intended only for the person or entity to
which it is addressed and may contain confidential and/or privileged
material. Any review, transmission, dissemination or other use of, or
taking of any action in reliance upon, this information by persons or
entities other than the intended recipient is prohibited. If you
received this in error, please contact the sender and delete the
material from any computers.
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------------------------------
Date: Tue, 15 Dec 2009 08:00:26 -0800
From: Jason Barta <jba...@URBAN-SYSTEMS.COM>
Subject: Re: Modeling Forcemains in SWMM5
Thanks gents. I have tried most of these options, but it's always nice
to learn a little theory.
Robert, I guess I didn't spell it out quite clearly, but I also noticed
the nice correlation as per your point number 6. However, if we look at
the node, one step further downstream, from the end of the forcemain,
the total flow is 0.183+/-, which is an additional 10 cubic meters (6%)
of flow coming from magic land.
Cheers,
Jason
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Robert Dickinson
Sent: December-15-09 1:12 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Hi Jason,
There is a great table in the SWMM 5 output file, the Node Inflow
Summary, that will show you both the lateral flow into a node and the
total inflow at the node. You can use this table to check the mass
balance between any two nodes of your network. If you check the total
inflow at the upstream node of your pump and the downstream node of your
forcemain you should see a good balance if you make the following
adjustments:
1. If you are simulating pumps that turn on very frequently you should
try using a 5 second time step or less,
2. I would suggest using a hotstart file to both lower any potential
continuity error and warm up your network faster,
3. It would be better to use BOTH as an option for normal flow as this
will trigger the normal flow equation for both water surface slope less
than the bed slope and a Froude number > 1 at either end of your links,
4. If you use KEEP as the inertial term option it will use all of the
terms in the St. Venant equation for partial flow, if the force main is
full the non-linear term will drop out anyway as both end of the link
have the same cross sectional area in this situation.
5. I would also suggest that you use the variable time step option just
in case the program needs to lower the routing time step sometime during
the simulation.
6. The total inflow of 0.173 at your loading node and the total node
inflow of 0.175 at the downstream end of the force main is very close
especially based on the number of times your pumps turn on during the
course of the simulation.
*******************
Node Inflow Summary
*******************
------------------------------------------------------------------------
-------------
Maximum Maximum
Lateral Total
Lateral Total Time of Max
Inflow Inflow
Inflow Inflow Occurrence
Volume Volume
Node Type LPS LPS days hr:min 10^6
ltr 10^6 ltr
------------------------------------------------------------------------
-------------
Best and Kind Regards,
Robert E Dickinson
Technical Engineering Specialist
MWH Soft, Inc
9340 Pontiac Drive Tel: 813-712-0664
Tampa, Florida, 33626 Alt: 813-494-2919
USA
robert.d...@mwhsoft.com
www.mwhsoft.com
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Brink, Philip
Sent: Monday, December 14, 2009 11:53 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Good; I would assume you would have already checked that, but sometimes
it's the simple or what should be obvious that can cause a perplexity. I
will also assume you have a fine-enough reporting interval so you aren't
missing any instability or peak flows that might be passing through as
well (but that'd be my next thought). You may want to post the file for
further input.
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 2:40 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
No. There is only the flow at the one node upstream of the pump station.
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Brink, Philip
Sent: December-14-09 11:34 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Do you possibly have some baseflow assigned at the pump station or at
the node(s) downstream?
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 1:30 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: [SWMM-USERS] Modeling Forcemains in SWMM5
I have constructed two hydraulic models for sanitary sewer systems and
am receiving the same odd results in both.
The cumulative net inflow into the pump station totals to a sum "x".
The cumulative net inflow at the downstream node of the forcemain is the
same value "x".
However, in the next node downstream from the forcemain, the net inflow
into the node is greater than "x".
There is only one source of flow in all of the network which is upstream
of the pump station.
What could be causing this mysterious "additional flow"?
I will not be able to predict residual capacity in the system with any
confidence unless this is resolved.
Thanks and have a great holiday season.
Disclaimer :
The information transmitted is intended only for the person or entity to
which it is addressed and may contain confidential and/or privileged
material. Any review, transmission, dissemination or other use of, or
taking of any action in reliance upon, this information by persons or
entities other than the intended recipient is prohibited. If you
received this in error, please contact the sender and delete the
material from any computers.
**********************************************************
* To sign off, email to: list...@listserv.uoguelph.ca *
* In the body of the message type: signoff swmm-users *
**********************************************************
**********************************************************
* To sign off, email to: list...@listserv.uoguelph.ca *
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**********************************************************
Disclaimer :
The information transmitted is intended only for the person or entity to
which it is addressed and may contain confidential and/or privileged
material. Any review, transmission, dissemination or other use of, or
taking of any action in reliance upon, this information by persons or
entities other than the intended recipient is prohibited. If you
received this in error, please contact the sender and delete the
material from any computers.
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The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, transmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please contact the sender and delete the material from any computers.
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------------------------------
Date: Tue, 15 Dec 2009 09:25:06 -0700
From: Robert Dickinson <Robert.E....@US.MWHGLOBAL.COM>
Subject: Re: Modeling Forcemains in SWMM5
Hi Jason, The model bears more examination but changing node 415 to a storage node will lower the flow in the downstream links to 0.177 million liter. There may be other alternatives to how you are modeling this particular node and downstream links (more links around the rising main for instance). I should have looked at the network in profile view - it explains the situation better than just looking at the node total flows.
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of Jason Barta
Sent: Tuesday, December 15, 2009 8:00 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Thanks gents. I have tried most of these options, but it's always nice
to learn a little theory.
Robert, I guess I didn't spell it out quite clearly, but I also noticed
the nice correlation as per your point number 6. However, if we look at
the node, one step further downstream, from the end of the forcemain,
the total flow is 0.183+/-, which is an additional 10 cubic meters (6%)
of flow coming from magic land.
Cheers,
Jason
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Robert Dickinson
Sent: December-15-09 1:12 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Hi Jason,
There is a great table in the SWMM 5 output file, the Node Inflow
Summary, that will show you both the lateral flow into a node and the
total inflow at the node. You can use this table to check the mass
balance between any two nodes of your network. If you check the total
inflow at the upstream node of your pump and the downstream node of your
forcemain you should see a good balance if you make the following
adjustments:
1. If you are simulating pumps that turn on very frequently you should
try using a 5 second time step or less,
2. I would suggest using a hotstart file to both lower any potential
continuity error and warm up your network faster,
3. It would be better to use BOTH as an option for normal flow as this
will trigger the normal flow equation for both water surface slope less
than the bed slope and a Froude number > 1 at either end of your links,
4. If you use KEEP as the inertial term option it will use all of the
terms in the St. Venant equation for partial flow, if the force main is
full the non-linear term will drop out anyway as both end of the link
have the same cross sectional area in this situation.
5. I would also suggest that you use the variable time step option just
in case the program needs to lower the routing time step sometime during
the simulation.
6. The total inflow of 0.173 at your loading node and the total node
inflow of 0.175 at the downstream end of the force main is very close
especially based on the number of times your pumps turn on during the
course of the simulation.
*******************
Node Inflow Summary
*******************
------------------------------------------------------------------------
-------------
Maximum Maximum
Lateral Total
Lateral Total Time of Max
Inflow Inflow
Inflow Inflow Occurrence
Volume Volume
Node Type LPS LPS days hr:min 10^6
ltr 10^6 ltr
------------------------------------------------------------------------
-------------
Best and Kind Regards,
Robert E Dickinson
Technical Engineering Specialist
MWH Soft, Inc
9340 Pontiac Drive Tel: 813-712-0664
Tampa, Florida, 33626 Alt: 813-494-2919
USA
robert.d...@mwhsoft.com
www.mwhsoft.com
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Brink, Philip
Sent: Monday, December 14, 2009 11:53 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Good; I would assume you would have already checked that, but sometimes
it's the simple or what should be obvious that can cause a perplexity. I
will also assume you have a fine-enough reporting interval so you aren't
missing any instability or peak flows that might be passing through as
well (but that'd be my next thought). You may want to post the file for
further input.
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 2:40 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
No. There is only the flow at the one node upstream of the pump station.
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Brink, Philip
Sent: December-14-09 11:34 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Do you possibly have some baseflow assigned at the pump station or at
the node(s) downstream?
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 1:30 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: [SWMM-USERS] Modeling Forcemains in SWMM5
I have constructed two hydraulic models for sanitary sewer systems and
am receiving the same odd results in both.
The cumulative net inflow into the pump station totals to a sum "x".
The cumulative net inflow at the downstream node of the forcemain is the
same value "x".
However, in the next node downstream from the forcemain, the net inflow
into the node is greater than "x".
There is only one source of flow in all of the network which is upstream
of the pump station.
What could be causing this mysterious "additional flow"?
I will not be able to predict residual capacity in the system with any
confidence unless this is resolved.
Thanks and have a great holiday season.
Disclaimer :
The information transmitted is intended only for the person or entity to
which it is addressed and may contain confidential and/or privileged
material. Any review, transmission, dissemination or other use of, or
taking of any action in reliance upon, this information by persons or
entities other than the intended recipient is prohibited. If you
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End of SWMM-USERS Digest - 14 Dec 2009 to 15 Dec 2009 (#2009-137)
*****************************************************************
Topics of the day:
1. Modeling Forcemains in SWMM5 (4)
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----------------------------------------------------------------------
Date: Tue, 15 Dec 2009 02:12:11 -0700
From: Robert Dickinson <Robert.E....@US.MWHGLOBAL.COM>
Subject: Re: Modeling Forcemains in SWMM5
Hi Jason,
There is a great table in the SWMM 5 output file, the Node Inflow Summary, =
that will show you both the lateral flow into a node and the total inflow a=
t the node. You can use this table to check the mass balance between any t=
wo nodes of your network. If you check the total inflow at the upstream no=
de of your pump and the downstream node of your forcemain you should see a =
good balance if you make the following adjustments:
1. If you are simulating pumps that turn on very frequently you should try=
using a 5 second time step or less,
2. I would suggest using a hotstart file to both lower any potential conti=
nuity error and warm up your network faster,
3. It would be better to use BOTH as an option for normal flow as this wil=
l trigger the normal flow equation for both water surface slope less than t=
he bed slope and a Froude number > 1 at either end of your links,
4. If you use KEEP as the inertial term option it will use all of the term=
s in the St. Venant equation for partial flow, if the force main is full th=
e non-linear term will drop out anyway as both end of the link have the sam=
e cross sectional area in this situation.
5. I would also suggest that you use the variable time step option just in=
case the program needs to lower the routing time step sometime during the =
simulation.
6. The total inflow of 0.173 at your loading node and the total node inflo=
w of 0.175 at the downstream end of the force main is very close especially=
based on the number of times your pumps turn on during the course of the s=
imulation.
*******************
Node Inflow Summary
*******************
-----------------------------------------------------------------------=
--------------
Maximum Maximum Lateral=
Total
Lateral Total Time of Max Inflow=
Inflow
Inflow Inflow Occurrence Volume=
Volume
Node Type LPS LPS days hr:min 10^6 ltr=
10^6 ltr
-------------------------------------------------------------------------=
------------
Best and Kind Regards,
Robert E Dickinson
Technical Engineering Specialist
MWH Soft, Inc
9340 Pontiac Drive Tel: 813-712-0664
Tampa, Florida, 33626 Alt: 813-494-2919
USA
robert.d...@mwhsoft.com
www.mwhsoft.com
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of Brin=
k, Philip
Sent: Monday, December 14, 2009 11:53 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Good; I would assume you would have already checked that, but sometimes
it's the simple or what should be obvious that can cause a perplexity. I
will also assume you have a fine-enough reporting interval so you aren't
missing any instability or peak flows that might be passing through as
well (but that'd be my next thought). You may want to post the file for
further input.
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 2:40 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
No. There is only the flow at the one node upstream of the pump station.
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Brink, Philip
Sent: December-14-09 11:34 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Do you possibly have some baseflow assigned at the pump station or at
the node(s) downstream?
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 1:30 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: [SWMM-USERS] Modeling Forcemains in SWMM5
I have constructed two hydraulic models for sanitary sewer systems and
am receiving the same odd results in both.
The cumulative net inflow into the pump station totals to a sum "x".
The cumulative net inflow at the downstream node of the forcemain is the
same value "x".
However, in the next node downstream from the forcemain, the net inflow
into the node is greater than "x".
There is only one source of flow in all of the network which is upstream
of the pump station.
What could be causing this mysterious "additional flow"?
I will not be able to predict residual capacity in the system with any
confidence unless this is resolved.
Thanks and have a great holiday season.
Disclaimer :
The information transmitted is intended only for the person or entity to
which it is addressed and may contain confidential and/or privileged
material. Any review, transmission, dissemination or other use of, or
taking of any action in reliance upon, this information by persons or
entities other than the intended recipient is prohibited. If you
received this in error, please contact the sender and delete the
material from any computers.
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------------------------------
Date: Tue, 15 Dec 2009 09:16:17 -0400
From: "Wilson, Alexander" <alexa...@CBCL.CA>
Subject: Re: Modeling Forcemains in SWMM5
Hi Jason,
To add my 2 cents to Bob's list, I had a similar experience, which was
resolved by removing
the conduit lengthening option (changed it to 0). It was artificially
creating volume in the system.
Alexander.
Alexander T. Wilson, M.Eng, P.Eng.
Water Resources Engineer
CBCL Limited, Consulting Engineers
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Robert Dickinson
Sent: Tuesday, December 15, 2009 5:12 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Hi Jason,
There is a great table in the SWMM 5 output file, the Node Inflow
Summary, that will show you both the lateral flow into a node and the
total inflow at the node. You can use this table to check the mass
balance between any two nodes of your network. If you check the total
inflow at the upstream node of your pump and the downstream node of your
forcemain you should see a good balance if you make the following
adjustments:
1. If you are simulating pumps that turn on very frequently you should
try using a 5 second time step or less,
2. I would suggest using a hotstart file to both lower any potential
continuity error and warm up your network faster,
3. It would be better to use BOTH as an option for normal flow as this
will trigger the normal flow equation for both water surface slope less
than the bed slope and a Froude number > 1 at either end of your links,
4. If you use KEEP as the inertial term option it will use all of the
terms in the St. Venant equation for partial flow, if the force main is
full the non-linear term will drop out anyway as both end of the link
have the same cross sectional area in this situation.
5. I would also suggest that you use the variable time step option just
in case the program needs to lower the routing time step sometime during
the simulation.
6. The total inflow of 0.173 at your loading node and the total node
inflow of 0.175 at the downstream end of the force main is very close
especially based on the number of times your pumps turn on during the
course of the simulation.
*******************
Node Inflow Summary
*******************
------------------------------------------------------------------------
-------------
Maximum Maximum
Lateral Total
Lateral Total Time of Max
Inflow Inflow
Inflow Inflow Occurrence
Volume Volume
Node Type LPS LPS days hr:min 10^6
ltr 10^6 ltr
------------------------------------------------------------------------
-------------
Best and Kind Regards,
Robert E Dickinson
Technical Engineering Specialist
MWH Soft, Inc
9340 Pontiac Drive Tel: 813-712-0664
Tampa, Florida, 33626 Alt: 813-494-2919
USA
robert.d...@mwhsoft.com
www.mwhsoft.com
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Brink, Philip
Sent: Monday, December 14, 2009 11:53 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Good; I would assume you would have already checked that, but sometimes
it's the simple or what should be obvious that can cause a perplexity. I
will also assume you have a fine-enough reporting interval so you aren't
missing any instability or peak flows that might be passing through as
well (but that'd be my next thought). You may want to post the file for
further input.
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 2:40 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
No. There is only the flow at the one node upstream of the pump station.
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Brink, Philip
Sent: December-14-09 11:34 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Do you possibly have some baseflow assigned at the pump station or at
the node(s) downstream?
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 1:30 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: [SWMM-USERS] Modeling Forcemains in SWMM5
I have constructed two hydraulic models for sanitary sewer systems and
am receiving the same odd results in both.
The cumulative net inflow into the pump station totals to a sum "x".
The cumulative net inflow at the downstream node of the forcemain is the
same value "x".
However, in the next node downstream from the forcemain, the net inflow
into the node is greater than "x".
There is only one source of flow in all of the network which is upstream
of the pump station.
What could be causing this mysterious "additional flow"?
I will not be able to predict residual capacity in the system with any
confidence unless this is resolved.
Thanks and have a great holiday season.
Disclaimer :
The information transmitted is intended only for the person or entity to
which it is addressed and may contain confidential and/or privileged
material. Any review, transmission, dissemination or other use of, or
taking of any action in reliance upon, this information by persons or
entities other than the intended recipient is prohibited. If you
received this in error, please contact the sender and delete the
material from any computers.
**********************************************************
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------------------------------
Date: Tue, 15 Dec 2009 08:00:26 -0800
From: Jason Barta <jba...@URBAN-SYSTEMS.COM>
Subject: Re: Modeling Forcemains in SWMM5
Thanks gents. I have tried most of these options, but it's always nice
to learn a little theory.
Robert, I guess I didn't spell it out quite clearly, but I also noticed
the nice correlation as per your point number 6. However, if we look at
the node, one step further downstream, from the end of the forcemain,
the total flow is 0.183+/-, which is an additional 10 cubic meters (6%)
of flow coming from magic land.
Cheers,
Jason
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Robert Dickinson
Sent: December-15-09 1:12 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Hi Jason,
There is a great table in the SWMM 5 output file, the Node Inflow
Summary, that will show you both the lateral flow into a node and the
total inflow at the node. You can use this table to check the mass
balance between any two nodes of your network. If you check the total
inflow at the upstream node of your pump and the downstream node of your
forcemain you should see a good balance if you make the following
adjustments:
1. If you are simulating pumps that turn on very frequently you should
try using a 5 second time step or less,
2. I would suggest using a hotstart file to both lower any potential
continuity error and warm up your network faster,
3. It would be better to use BOTH as an option for normal flow as this
will trigger the normal flow equation for both water surface slope less
than the bed slope and a Froude number > 1 at either end of your links,
4. If you use KEEP as the inertial term option it will use all of the
terms in the St. Venant equation for partial flow, if the force main is
full the non-linear term will drop out anyway as both end of the link
have the same cross sectional area in this situation.
5. I would also suggest that you use the variable time step option just
in case the program needs to lower the routing time step sometime during
the simulation.
6. The total inflow of 0.173 at your loading node and the total node
inflow of 0.175 at the downstream end of the force main is very close
especially based on the number of times your pumps turn on during the
course of the simulation.
*******************
Node Inflow Summary
*******************
------------------------------------------------------------------------
-------------
Maximum Maximum
Lateral Total
Lateral Total Time of Max
Inflow Inflow
Inflow Inflow Occurrence
Volume Volume
Node Type LPS LPS days hr:min 10^6
ltr 10^6 ltr
------------------------------------------------------------------------
-------------
Best and Kind Regards,
Robert E Dickinson
Technical Engineering Specialist
MWH Soft, Inc
9340 Pontiac Drive Tel: 813-712-0664
Tampa, Florida, 33626 Alt: 813-494-2919
USA
robert.d...@mwhsoft.com
www.mwhsoft.com
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Brink, Philip
Sent: Monday, December 14, 2009 11:53 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Good; I would assume you would have already checked that, but sometimes
it's the simple or what should be obvious that can cause a perplexity. I
will also assume you have a fine-enough reporting interval so you aren't
missing any instability or peak flows that might be passing through as
well (but that'd be my next thought). You may want to post the file for
further input.
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 2:40 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
No. There is only the flow at the one node upstream of the pump station.
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Brink, Philip
Sent: December-14-09 11:34 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Do you possibly have some baseflow assigned at the pump station or at
the node(s) downstream?
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 1:30 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: [SWMM-USERS] Modeling Forcemains in SWMM5
I have constructed two hydraulic models for sanitary sewer systems and
am receiving the same odd results in both.
The cumulative net inflow into the pump station totals to a sum "x".
The cumulative net inflow at the downstream node of the forcemain is the
same value "x".
However, in the next node downstream from the forcemain, the net inflow
into the node is greater than "x".
There is only one source of flow in all of the network which is upstream
of the pump station.
What could be causing this mysterious "additional flow"?
I will not be able to predict residual capacity in the system with any
confidence unless this is resolved.
Thanks and have a great holiday season.
Disclaimer :
The information transmitted is intended only for the person or entity to
which it is addressed and may contain confidential and/or privileged
material. Any review, transmission, dissemination or other use of, or
taking of any action in reliance upon, this information by persons or
entities other than the intended recipient is prohibited. If you
received this in error, please contact the sender and delete the
material from any computers.
**********************************************************
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* In the body of the message type: signoff swmm-users *
**********************************************************
**********************************************************
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material. Any review, transmission, dissemination or other use of, or
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entities other than the intended recipient is prohibited. If you
received this in error, please contact the sender and delete the
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------------------------------
Date: Tue, 15 Dec 2009 09:25:06 -0700
From: Robert Dickinson <Robert.E....@US.MWHGLOBAL.COM>
Subject: Re: Modeling Forcemains in SWMM5
Hi Jason, The model bears more examination but changing node 415 to a storage node will lower the flow in the downstream links to 0.177 million liter. There may be other alternatives to how you are modeling this particular node and downstream links (more links around the rising main for instance). I should have looked at the network in profile view - it explains the situation better than just looking at the node total flows.
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of Jason Barta
Sent: Tuesday, December 15, 2009 8:00 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Thanks gents. I have tried most of these options, but it's always nice
to learn a little theory.
Robert, I guess I didn't spell it out quite clearly, but I also noticed
the nice correlation as per your point number 6. However, if we look at
the node, one step further downstream, from the end of the forcemain,
the total flow is 0.183+/-, which is an additional 10 cubic meters (6%)
of flow coming from magic land.
Cheers,
Jason
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Robert Dickinson
Sent: December-15-09 1:12 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Hi Jason,
There is a great table in the SWMM 5 output file, the Node Inflow
Summary, that will show you both the lateral flow into a node and the
total inflow at the node. You can use this table to check the mass
balance between any two nodes of your network. If you check the total
inflow at the upstream node of your pump and the downstream node of your
forcemain you should see a good balance if you make the following
adjustments:
1. If you are simulating pumps that turn on very frequently you should
try using a 5 second time step or less,
2. I would suggest using a hotstart file to both lower any potential
continuity error and warm up your network faster,
3. It would be better to use BOTH as an option for normal flow as this
will trigger the normal flow equation for both water surface slope less
than the bed slope and a Froude number > 1 at either end of your links,
4. If you use KEEP as the inertial term option it will use all of the
terms in the St. Venant equation for partial flow, if the force main is
full the non-linear term will drop out anyway as both end of the link
have the same cross sectional area in this situation.
5. I would also suggest that you use the variable time step option just
in case the program needs to lower the routing time step sometime during
the simulation.
6. The total inflow of 0.173 at your loading node and the total node
inflow of 0.175 at the downstream end of the force main is very close
especially based on the number of times your pumps turn on during the
course of the simulation.
*******************
Node Inflow Summary
*******************
------------------------------------------------------------------------
-------------
Maximum Maximum
Lateral Total
Lateral Total Time of Max
Inflow Inflow
Inflow Inflow Occurrence
Volume Volume
Node Type LPS LPS days hr:min 10^6
ltr 10^6 ltr
------------------------------------------------------------------------
-------------
Best and Kind Regards,
Robert E Dickinson
Technical Engineering Specialist
MWH Soft, Inc
9340 Pontiac Drive Tel: 813-712-0664
Tampa, Florida, 33626 Alt: 813-494-2919
USA
robert.d...@mwhsoft.com
www.mwhsoft.com
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Brink, Philip
Sent: Monday, December 14, 2009 11:53 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Good; I would assume you would have already checked that, but sometimes
it's the simple or what should be obvious that can cause a perplexity. I
will also assume you have a fine-enough reporting interval so you aren't
missing any instability or peak flows that might be passing through as
well (but that'd be my next thought). You may want to post the file for
further input.
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 2:40 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
No. There is only the flow at the one node upstream of the pump station.
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Brink, Philip
Sent: December-14-09 11:34 AM
To: SWMM-...@listserv.uoguelph.ca
Subject: Re: [SWMM-USERS] Modeling Forcemains in SWMM5
Jason,
Do you possibly have some baseflow assigned at the pump station or at
the node(s) downstream?
Phil
Philip N. Brink, P.E.
CDM Michigan Inc.
Direct 313.230.5624
-----Original Message-----
From: SWMM-USERS [mailto:SWMM-...@listserv.uoguelph.ca] On Behalf Of
Jason Barta
Sent: Monday, December 14, 2009 1:30 PM
To: SWMM-...@listserv.uoguelph.ca
Subject: [SWMM-USERS] Modeling Forcemains in SWMM5
I have constructed two hydraulic models for sanitary sewer systems and
am receiving the same odd results in both.
The cumulative net inflow into the pump station totals to a sum "x".
The cumulative net inflow at the downstream node of the forcemain is the
same value "x".
However, in the next node downstream from the forcemain, the net inflow
into the node is greater than "x".
There is only one source of flow in all of the network which is upstream
of the pump station.
What could be causing this mysterious "additional flow"?
I will not be able to predict residual capacity in the system with any
confidence unless this is resolved.
Thanks and have a great holiday season.
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End of SWMM-USERS Digest - 14 Dec 2009 to 15 Dec 2009 (#2009-137)
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