Pump modelling issue in Sewer network

Question

Hi, I have modelled an existing sewer network which has 3 pump stations. I have followed existing sample of software but pumps and pressure pipes had no flow. There is no error or big issue at modelling but there is no flow in under pressure pipes. I am seeking for your advice. 
 Cheers, Omid

Sushma Choure · Accepted Answer

Hello Omid, 
 Thanks for uploading the model files. 
 Which software / which solver are you using? 
 &bull; For the pump modeling you better be using GVF- Convex solver, so you should have pump and wet-well connected with a pressure pipe not the conduit. 
 &bull; You are using Implicit solver; do you want to analyze the model for steady start or EPS? 
 &bull; You haven&rsquo;t defined wet well&rsquo;s operating range, so you are not getting the results, please define that and update the pump ON/off elevations accordingly., then there is flow in the model through pressure pipes and PMP-7 at time step 20.00 hrs for implicit solver. 
 &bull; I looked at the wet well W-2 and pump PMP-7, pump definition is not correct when compared it with the required head and the flow, the pump needs to add around 15 m head, so please recheck your pump curve. That is causing overflow at wet-well W-2. 
 &bull; Please check the above-mentioned points for all the wet wells and pumps. 
 &bull; To check what pump definition to choose, you can look at the system head curve which will guide you to select the pump curve, this is available for GVF- Convex solver, not for the implicit. 
 Here is detailed information on system head curves. 
 http://communities.bentley.com/products/hydraulics___hydrology/w/hydraulics_and_hydrology__wiki/16879.estimating-a-pump-curve-for-a-model 
 http://communities.bentley.com/products/hydraulics___hydrology/w/hydraulics_and_hydrology__wiki/24627.system-head-curves-in-watergems-and-watercad 
 If we are making these changes in the model, we get the flow through pressure pipes as well.

MPachlhofer · Answer

Omid, 
 
Please refer to the solution in your other forum post found here for a solution: 
 
 communities.bentley.com/.../393892 
 
Regards, 
Mark