Centrifugal pump analysis
 

I am analyzing a multistage pump in fluent, my solution does not converge, but the results for head and fluxes are logical, but when i am checking pressure or velocity contour when the autorange is active , the contours are just blue or only red, the maximum range is to high, when i deactivate the autorange, and modifying the max range to a smaller amount the contours apears right, also in my run the k and epsilon oscillates in accuracy of 10^-1. Can any one help with this problem? Shall i change the under relaxation factor? , this will effect on my answers. My boundary conditions are mass inlet and pressure outlet and the pump is 7 stage

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