[arashm]

hello everyone,

I'm trying to design a tidal turbine, the pricinples are the same as wind turbine. The design process consists of dividing the rotor blade into n section and find the angle of attack and lift coefficient of each of them. I've done that and now I'm trying to analyze by FLUENT one of these sections which is a NACA0012 airfoil . I need to obtain the lift coefficient in order to show the grid independece, but sometimes FLUENT gives me funny results. For example for my coarser grid let's say I obtain 0.12 for the lift coefficient but with the same geometry and conditions with a finer grid, FLUENT shows me -1.#IND for that. I've checked many times but still I get the same. Does anyone know what -1.#IND mean ?
Thank you,