I am trying to create flow simulation of existing fan design. I have real-life lab test that I like to compare the accuracy of this simulation, but the result is far different from real-life test. Below is my summery of test:
- Visialize air flow in 1.8m in front of fan blades, width 1.5m
- Find target wind speed at 75cm in front of fan blade, (done same things in real lab test, so I can compare them)
Problem on simulation result:
- The wind flow pic (trajectories) look different from different refinement level. I think my cell on solid-fluid, small gap, and the blade itselt is fine enough. But, I cant tell if this is refect to reality, I cant tell which/where the refinement is need in order to optimize the result that is close to real situation.
- Whatever resolution (or refinement level or cell) that I have set, the wind speed at 75cm location is far different from real lab test. (the lab result is around 1.3-1.6m/s, but simulation is only around 0.1-0.5m/s) At this point, I don’t quite believe on the trajectories result becauase the wind speed is dfifneret from real-life lab test
I have different set of refinement setting, and only keep all atmosphere pressure and density the same, rotation at fan blade is 800rpm, and all the goals is about velocity and z velocity in average + bulk. But all goals I set not to ‘use for convergence control’ because I don’t the calculation stop at any point so that I can visialize the whole air flow)
- Why with differnet refinement level setting, the wind speed result is still far different from real-lifel ab test?
- Could anyone suggest a right strategy on setting refinement level, so I know everytime when I update the cell, I can tell the new one is always better then old one, and my experiement is always a step closer to the reality.
- Is anything other than cell/refinement level I set it wrong so that my wind speed result is different? Such as atmosphere pressure or density or anything?
attached pic are all my setting and result of final-try: