Dear All,
I would appreciate your help with pump performance simulation. I am working on project https://www.simscale.com/workbench/?pid=3382419860169863602&mi=run%3A112%2Csimulation%3A12&mt=SIMULATION_RUN
Runs 5 and 6. The calculation of head has given very good results at different speeds and flow rates. But the efficiency is significantly overestimated (about 20% higher, than experimental data). It means that torque values are lower than they should be. I use the value of Pressure moment x for topological entity set “Impeller” as torque. What can be a reason of such mismatch? I think that maybe it needs to take into account the motor shaft, but I don’t see how to do it. Something else?
Another problem is the axial thrust calculation. The values those I have are very far from test data those I have. I define the thrust as pressure force x for “Impeller”. But even the force direction seems to me strange: I have positive force on front shroud (X force on topological entity set “front shroud”) and negative on rear shroud and inside rear shroud sealing (X force on topological entity sets “rear shroud” and “chamber”), but accordingly axe direction it must be an opposite direction! What is wrong in this case?
Thank you in advance for any help.