Before revision: The magnitude of deflection depends upon the following: (a) stiffness of the shaft and its support (b) total mass of shaft and attached parts (c) unbalance of the mass with respect to the axis of rotation (d) the amount of damping in the system In general, it is necessary to calculate the critical speed of a rotating shaft, such as a fan shaft, in order to avoid issues with noise and vibration.
After revision: The magnitude of deflection depends upon the following: Stiffness of the shaft and its support Total mass of shaft and attached parts Unbalance of the mass with respect to the axis of rotation The amount of damping in the system In general, it is necessary to calculate the critical speed of a rotating shaft, such as a fan shaft, in order to avoid issues with noise and vibration.