Hello everyone, <\/p>\n
I’m a master’s student and relatively new to Ansys Fluent. Since September, I have been learning how to use it from scratch by myself. <\/p>\n
I’m writing this post because I’m struggling to let my simulation for an abrupt expansion pipe converge. <\/p>\n
The geometry of my abrupt expansion pipe is like this: <\/p>\n
Mesh qualities:
– Minimum Orthogonal Quality: 0.16
– Maximum skewness: 0.39
(According to the manual, these qualities seem to be okay, though it’s not that good.)<\/p>\n
The setup in Fluent that I did is the following: <\/p>\n
Solver setting in General:
– Type: Pressure-Based
– Velocity Formulation: Absolute
– Time: Steady<\/p>\n
Since the flow is laminar(Re for the thin pipe = 2000, Re for the thick pipe = 666), I choose the Laminar model. <\/p>\n
Boundary conditions:
– Inlet velocity = 0.172 m\/s
– Outlet pressure: Gauge pressure = 0 Pa<\/p>\n
When I set smaller inlet velocity (0.001 m\/s, 0.003 m\/s, 0.005 m\/s, 0.011 m\/s, 0.021 m\/s, 0.043 m\/s), the simulation successfully converged. However, with a larger inlet velocity like this time (0.172 m\/s), the simulation no longer converges… <\/p>\n
I tried the following solutions, but none worked well:
– Increase the number of iterations
– Change fluid time scale
– Change relaxation factors<\/p>\n
I have been trying my best to think about possible solutions by myself, but unfortunately, I have not succeeded. I would appreciate it if some of you could give me possible suggestions. <\/p>\n","protected":false},"template":"","class_list":["post-318728","topic","type-topic","status-closed","hentry","topic-tag-convergence-issue","topic-tag-laminar-flow","topic-tag-laminar-pipe-flow-1"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t