Dear Jesse,
Thanks for your earlier reply. it really helped me. but now i am facing another problem. when i am modelling a ground storage tank in rising main, it effects the hydraulic grade line of all previous nodes. how can i avoid this.
and if i change the elevations to higher elevations (which are not the actual ones) its make impact and negative pressure changes to positive pressure. how can i avoid the effect on previous node because i have free falling water to ground storage tank.
Suhail Latif
Regards,
Sushma Choure
Bentley Technical Suppport
4382.1780.Model.rar
Reply from Suhail , posted by mistake in a new post -
Hello Ms Sushma,
i am attaching the model for your review. actually tanks affecting the hydraulic grade line of previous nodes, if i removed the tank the i got very smooth line. tank is under ground tank and inlet is on top. so it should not affect the previous nodes .
Answer Verified By: Sushma Choure
As Sushma pointed out, a tank is a boundary condition in WaterCAD and WaterGEMS, essentially specifying a known hydraulic grade from which the solves other hydraulic grades.
If your tank fills from the top, and the boundary HGL of the water water surface effects only the downstream side, then you could use the top-filling tank feature in place of the air valve node. You can read more about it here:
Modeling top fill tanks and throttling inlet valves
However, I noticed that the maximum elevation in your tank (408 ft) is less than the elevation of the upstream node (J-14, at 410 ft).
If you use the air valve approach, you can read more about its use in a steady state/EPS here:
Modeling Air Valves At High Points in WaterCAD or WaterGEMS
Jesse DringoliTechnical Support Manager, OpenFlowsBentley Communities Site AdministratorBentley Systems, Inc.