To perform a trustworthy simulation of the motor of an AC fan in a transient analysis, you should have to take into account the load (the effect of drag on the helix blades), and the Lorentz effect on the equivalent electric circuit; that is, unless you want a simpler steady state model at its terminal rotational velocity, you can get this information empirically by measuring the power factor and the current load, which can be represented only by a resistive and a series inductive load.