|February 28, 2014, 04:00||
Convergence issues for a 3D Centrifugal pump simulation using ANSYS CFX
Join Date: Nov 2009
Posts: 35Rep Power: 7
Am currently solving a steady state 3D Centrifugal pump problem using ANSYS CFX.
To validate the performance curve of pump based on experimental inputs
Stationary domain: Inlet, Outlet and Casing (1 Body)
Rotating domain: Impeller fluid volume surrounding the solid impeller. But solid impeller trace is left within the impeller fluid volume
Domain interface: Between Stationary domain and rotating domain.
Method: SRF and Frozen Rotor with no pitch change
Fine On curvature with skewness of 0.92 and Aspect ratio of 60
Boundary conditions used:
Domain ref pressure = 1 bar.
Inlet: Total pressure = 0 bar
Outlet: Mass flow rate = 0.065 kg/s or 3.9 lpm.
Turbulence intensity: Medium
Heat transfer: none
Rotating domain: 3100 RPM about Global Y
Convergence beyond 1E-3 seem to be impossible with lot of wiggles Number of iterations: 700; Criteria: Want to set 1E-6 but I set it to default for first run.
If I consider the heat transfer, I get similar behavior. My idea is to consider the temperature later when I get the desired pressure rise.
I tried various combinations of BCs. Gone through previous threads.
It was so tricky to get the solution converged even if I use thumb rule of 1/2w , 1/4w....as physical timescale. Checked with automatic timescale in the beginning.
After 290 iterations, flow is getting blocked at inlet and outlet with changes in block % ranging from 0.5 % to 67%
Any suggestions or discussions related to this matter is highly appreciated.
Please find attached the current status as images:
|Thread||Thread Starter||Forum||Replies||Last Post|
|Small cluster configuration for pump simulation at CFX||Nevel||Hardware||2||April 7, 2014 06:07|
|centrifugal pump simulation OK but result with 30% error||ARohit||FLUENT||0||January 1, 2014 02:54|
|ANSYS CFX simulation: Post CFX error||MInXD||CFX||3||May 19, 2013 19:24|
|How the way I can find efficiency of centrifugal pump from CFX||tttonggg||CFX||2||March 25, 2012 06:29|
|CFX convergence issues with free surface||adenlan||CFX||3||September 2, 2011 06:43|