NV Dynamics was engaged by M/s. Bajaj Electricals Limited to perform vibration analysis and determine the natural frequencies on selected models of ceiling fans. These natural frequencies are further used for conducting accelerated testing of the fan blades to simulate potential fan failures.
To facilitate this, three uniaxial accelerometers were fixed to the fan blades near the hub-blade junction, at the midspan and near the blade tip. Additionally, a uniaxial accelerometer was installed on the fan's hub. These accelerometers were connected to a multi-channel data acquisition system. Impact tests were conducted using a force hammer to excite the fan's natural frequencies, allowing the determination of the vibration characteristics of both the hub and blades.
For operational vibration analysis, a uniaxial accelerometer was mounted on the fan's support rod in close proximity to the bearing. This setup allowed for the collection of vibration acceleration data across various operational speeds. The collected data was subsequently analysed to extract the frequency and amplitude of the vibrations generated during fan operation.