HI, I am trying to run a distribution model in EPS in which the source is a over head tank on the hillock which serves a colony in which every building consists of a service overhead tank. But when I run this model flow is getting multiplied and not showing the actual hydraulics. Can you help me in thisTWS all Tank.wtg I attached the model also for your reference.
Thanks in advance,
Eswar
Hello Eswar
You have uploaded only .wtg file, please upload .wtg.sqlite file as well without which the model cannot be opened.
How are you modeling building service overhead tanks, you could put a junction for this with total demand of the building.
Regards,
Sushma Choure
Bentley Technical Suppport
Hi Sushma
Sorry for that,Herewith I am attaching the Whole model All Tanks.zip
I need the tank level for each passing hour of each building over head tank, that's why I modeled it as a Tank.
Thanks
Hello,
Could you give us an example in the model of the results you are looking at?
Also, I notice that you have a lot of tanks with demands associated with them. Is this as designed? What do these represent?
Scott
Hi,
All the tanks in the model represents over head tanks of every building in a colony, and it had the associated building demands in it. As I said earlier all the overhead tanks will get the supply from a balancing reservoir.
I want each tank percent full (%) at every hour in the EPS so that I can control the flow in the system.
A couple of first thoughts:
1) When I run the model, I get errors at a number of timesteps that the network is unbalanced, so it is not able to properly solve the hydraulic equations.
2) The first timestep that happens is at 4:00. From the demand patterns, it looks like this is also the time that you first have demand starting in the system. So from 0:00 - 4:00, it looks like there is zero demand and the flow is all from tanks filling. Most tanks are getting completely full in this time period, although a handful haven't yet filled all the way. Then at 4:00, residential demand starts ramping up, and I think what is happening is that some or all of the PRVs are struggling with how to calculate pressures with lots of full tanks plus demand on those tanks.
3) If you convert all the PRVs to junctions, the model runs without errors, and there aren't those crazy jumps in flows that come from unbalanced equations. However, that doesn't accurately model your system, because those PRVs are important. So experimenting with ways to make the PRVs give stable results is probably what is needed. I'll play around with this a bit more, but my first thought would be putting a small constant demand in each of the zones downstream of the PRVs, so that there is always a little bit of flow. That trick has worked for me in the past.