Subject: LP solver and exact reservoir releases Posted: 2/26/2012 Viewed: 28007 times
Hello,
is there any way to disable the lp solver?
i have three reservoirs, connected serialy and i want to determine the exact amount of water released from each one of them. i tried to determine the release by using target requirements below every reservoir but due to the lp solver the targets dont represent the exact release of eash dam.
Tell me if i am wrong but i think that if the lp solver is disabled the target requirements which are downstream of the reservoirs will represent the exact release. Is there any other way to determine the exact release?
Mr. Jack Sieber
Subject: Re: LP solver and exact reservoir releases Posted: 2/27/2012 Viewed: 27994 times
Ioannis,
No, there is no way to disable the LP solver—it does not just determine how much water is allocated to each demand but it also determines all the flows in the system.
WEAP will only release water from a reservoir to meet a downstream demand, unless the reservoir level goes above the Top of Conservation (TOC) level, in which case all water above TOC is released. Make sure the flow requirements below each reservoir are a higher priority than the reservoir itself. And if you make the priorities of the upstream reservoirs and flow requirements higher than the downstream ones, WEAP will not release water from one reservoir to fill up another reservoir. If you still cannot get it to behave as you want, please send me the WEAP area and I will take a look at it.
Jack
Dr. Mehdi Mirzaee
Subject: Re: LP solver and exact reservoir releases Posted: 3/22/2012 Viewed: 27882 times
Hi
Directly, you can not do that. But always there is a "way" :)
As Jack said, you can change priorities.
The other way, which is almost like above, is make some dummy demand nodes with consumption "0". These dummy nodes virtually force LP to release water from the first dam. Then you can link this dummy nodes to the upstream of the second dam, by a return flow. Then repeat this pattern to the other dams.
I am pretty sure that you know, there are some interesting functions in Expression builder that you can control water release, transmission, etc.
try to make a combination of dummy nodes and expression builder.
