modelling a borehole
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a.o...@mail.com
Aug 17, 2011, 6:26:11 AM8/17/11
to Epanet and Development
Hello,
RESERVOIR PUMP COMBINATION
Trying to model a proposed water collector system. Source is a
borehole, pipe diameters known, tank capacity and elevation known, but
i can't seem to represent a reservoir- pump system to discharge at a
certain rate and head.
wat factors go into assigning de reservoir head?..is it elevation of
borehole bottom? wat if dat isn't known...but there exists
SWL,DWL,ground surface elevation....
Any asistance
RESERVOIR PUMP COMBINATION
Trying to model a proposed water collector system. Source is a
borehole, pipe diameters known, tank capacity and elevation known, but
i can't seem to represent a reservoir- pump system to discharge at a
certain rate and head.
wat factors go into assigning de reservoir head?..is it elevation of
borehole bottom? wat if dat isn't known...but there exists
SWL,DWL,ground surface elevation....
Any asistance
a.o...@mail.com
Aug 17, 2011, 6:37:57 AM8/17/11
to Epanet and Development
Santiago Arnalich
Aug 18, 2011, 7:06:38 AM8/18/11
to epa...@googlegroups.com
Hi
These are actually two ways of doing it.
If you use the pump in the orthodox way, then the head of the pump is the drawdown + the difference in altitude from SWL to delivery point + pipe friction + velocity head.
So what you do is input in epanet's pump curve the first two terms. The last, the velocity head is usually negligeble. And the third depends on the pipe diameter, that is what you are trying to find out with epanet. So you try different diameters and different delivery heads until you have the pipe-pump combination you want.
Notice that you can save on the pipes and spendon pumping costs or invest in pipes and save in pumping and all the alternatives in between. So the decision is yours and epanet only tells you about pipe and pump pairs that go well together.
The reservoir alternative is an artifice, you still need the pump in real life! The only thing you do is set the head of the reservoir to match that of the pump. The idea is to simplify things by worrying first about the network, and once everything is correct, undo the change to find the pump or size it with charts. Sometimes trying to solve the network and the pumps at the same time is difficult if you dont have the experience.
I hope it resoved your questions
Santiago Arnalich
Coordinador
+34 950 16 72 17
+34 671700686
skype: sarnalich
...
www.arnalich.com
Consultancy & training for Development
These are actually two ways of doing it.
If you use the pump in the orthodox way, then the head of the pump is the drawdown + the difference in altitude from SWL to delivery point + pipe friction + velocity head.
So what you do is input in epanet's pump curve the first two terms. The last, the velocity head is usually negligeble. And the third depends on the pipe diameter, that is what you are trying to find out with epanet. So you try different diameters and different delivery heads until you have the pipe-pump combination you want.
Notice that you can save on the pipes and spendon pumping costs or invest in pipes and save in pumping and all the alternatives in between. So the decision is yours and epanet only tells you about pipe and pump pairs that go well together.
The reservoir alternative is an artifice, you still need the pump in real life! The only thing you do is set the head of the reservoir to match that of the pump. The idea is to simplify things by worrying first about the network, and once everything is correct, undo the change to find the pump or size it with charts. Sometimes trying to solve the network and the pumps at the same time is difficult if you dont have the experience.
I hope it resoved your questions
Santiago Arnalich
Coordinador
+34 950 16 72 17
+34 671700686
skype: sarnalich
...
www.arnalich.com
Consultancy & training for Development
--
www.arnalich.com
To send a message to the group, email: epa...@googlegroups.com
To unsubscribe, send a message to: epanetD+u...@googlegroups.com
a.o...@mail.com
Aug 18, 2011, 8:40:26 AM8/18/11
to Epanet and Development
I just had a break through ..
Head of the reservoir i used was actually the SWL- Drawdown-losses
Then included a pump with a pump curve with head(TWL-DWL) and Q being
the safe yield of the well.
And it's workin good...thanks for your input
On Aug 18, 11:06 am, Santiago Arnalich <coordinac...@arnalich.com>
wrote:
> Santiago Arnalich
> Coordinador
> +34 950 16 72 17begin_of_the_skype_highlighting +34 950 16 72 17
> +34 671700686begin_of_the_skype_highlighting +34 671700686
> skype: sarnalich
> ...www.arnalich.com
>
> - Show quoted text -
Head of the reservoir i used was actually the SWL- Drawdown-losses
Then included a pump with a pump curve with head(TWL-DWL) and Q being
the safe yield of the well.
And it's workin good...thanks for your input
On Aug 18, 11:06 am, Santiago Arnalich <coordinac...@arnalich.com>
wrote:
> Hi
>
> These are actually two ways of doing it.
>
> If you use the *pump* in the orthodox way, then the head of the pump is the
>
> These are actually two ways of doing it.
>
> drawdown + the difference in altitude from SWL to delivery point + pipe
> friction + velocity head.
>
> So what you do is input in epanet's pump curve the first two terms. The
> last, the velocity head is usually negligeble. And the third depends on the
> pipe diameter, that is what you are trying to find out with epanet. So you
> try different diameters and different delivery heads until you have the
> pipe-pump combination you want.
>
> Notice that you can save on the pipes and spendon pumping costs or invest in
> pipes and save in pumping and all the alternatives in between. So the
> decision is yours and epanet only tells you about pipe and pump pairs that
> go well together.
>
> The *reservoir* alternative is an artifice, you still need the pump in real
> friction + velocity head.
>
> So what you do is input in epanet's pump curve the first two terms. The
> last, the velocity head is usually negligeble. And the third depends on the
> pipe diameter, that is what you are trying to find out with epanet. So you
> try different diameters and different delivery heads until you have the
> pipe-pump combination you want.
>
> Notice that you can save on the pipes and spendon pumping costs or invest in
> pipes and save in pumping and all the alternatives in between. So the
> decision is yours and epanet only tells you about pipe and pump pairs that
> go well together.
>
> life! The only thing you do is set the head of the reservoir to match that
> of the pump. The idea is to simplify things by worrying first about the
> network, and once everything is correct, undo the change to find the pump or
> size it with charts. Sometimes trying to solve the network and the pumps at
> the same time is difficult if you dont have the experience.
>
> I hope it resoved your questions
>
> <http://www.arnalich.com/>
> of the pump. The idea is to simplify things by worrying first about the
> network, and once everything is correct, undo the change to find the pump or
> size it with charts. Sometimes trying to solve the network and the pumps at
> the same time is difficult if you dont have the experience.
>
> I hope it resoved your questions
>
> Santiago Arnalich
> Coordinador
> +34 950 16 72 17begin_of_the_skype_highlighting +34 950 16 72 17
> +34 671700686begin_of_the_skype_highlighting +34 671700686
> skype: sarnalich
> ...www.arnalich.com
> Consultancy & training for Development
>
>
>
> On Wed, Aug 17, 2011 at 12:37 PM, <a.ow...@mail.com> wrote:
>
> > On Aug 17, 10:26 am, a.ow...@mail.com wrote:
> > > Hello,
>
> > > RESERVOIR PUMP COMBINATION
> > > Trying to model a proposed water collector system. Source is a
> > > borehole, pipe diameters known, tank capacity and elevation known, but
> > > i can't seem to represent a reservoir- pump system to discharge at a
> > > certain rate and head.
>
> > > wat factors go into assigning de reservoir head?..is it elevation of
> > > borehole bottom? wat if dat isn't known...but there exists
> > > SWL,DWL,ground surface elevation....
>
> > > Any asistance
>
> > --
> >www.arnalich.com
>
> > To send a message to the group, email: epa...@googlegroups.com
>
> > To unsubscribe, send a message to: epanetD+u...@googlegroups.com- Hide quoted text -
>
>
>
> On Wed, Aug 17, 2011 at 12:37 PM, <a.ow...@mail.com> wrote:
>
> > On Aug 17, 10:26 am, a.ow...@mail.com wrote:
> > > Hello,
>
> > > RESERVOIR PUMP COMBINATION
> > > Trying to model a proposed water collector system. Source is a
> > > borehole, pipe diameters known, tank capacity and elevation known, but
> > > i can't seem to represent a reservoir- pump system to discharge at a
> > > certain rate and head.
>
> > > wat factors go into assigning de reservoir head?..is it elevation of
> > > borehole bottom? wat if dat isn't known...but there exists
> > > SWL,DWL,ground surface elevation....
>
> > > Any asistance
>
> > --
> >www.arnalich.com
>
> > To send a message to the group, email: epa...@googlegroups.com
>
>
> - Show quoted text -
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