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pokhrel February 20, 2017 16:45

VOF Grid Independence Test
 
5 Attachment(s)
Hello Everyone,
I am simulating a newly developed cross-flow water turbine using VOF and MRF models (three dimensional).
My concern is a power output from turbine. I calculated power which I believe is accurate output. Now I want to conduct Grid Independent Test in order to verify the result. I prepared seven different meshes to test, number of grid points ranging from 100,000 to 6,400,000 (100000,200000,400000,800000,1600000,3200000 and 6400000). I graphed instantaneous values of output power to compare the result. But what I found is, only three of seven graphs look alike. Other four (two with least number of grid points and two with most number of grid points) graphs look deviated. I have attached some of the graphs below.
However, if I look contour of volume fraction of water for all cases, flow looks correct and promising.
I it wise to accept the simulation and move forward with these results?


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