Dear Panagiotis,
By “inviscid”, do you mean that you set the drag to zero or something else?
I wouldn’t expect AeroDyn v14 input parameter AToler to effect the results of DYNIN, as this input is only used in the EQUIL solution. We normally recommend setting AToler to 0.005, which seems consistent with your results as well.
As discussed briefly in the following forum topic, under steady conditions, both EQUIL and DYNIN would ideally predict the same response, but this is not true in practice: question concerning TurbSim (V1.5) - #6 by Jason.Jonkman. However, your results are showing much bigger differences between EQUIL and DYNIN than I would normally expect. I expect that you doing something wrong in the simulation or in the interpretation of the results, but I don’t know what that might be. The DYNIN model is known to be numerically unstable for heavily loaded rotors (i.e. low wind speeds). Your simulation is close to this at 10 m/s; do you experience the same differences between EQUIL and DYNIN for higher operational wind speeds?
Our typical recommendation is to use EQUIL for simulations involving an operational wind turbine below rated wind speed and DYNIN for simulations involving an operational wind turbine above rated speed.
Best regards,