Experimental and Computational Study of Simply Supported Thin Rectangular Plate under Forced Vibrations

Experimental and numerical study was done to observe the response of undamped, simply supported thin plate under forced vibrations. After generating hexahedral mesh elements and applying simply supported boundary condition, two-dimensional numerical analysis was performed. First twenty natural frequencies of thin Aluminum rectangular plate having dimensions:
$200\text{mm}\times 250\text{mm}\times 1\text{mm}$
were calculated by performing modal analysis on ANSYS. Indigenous experimental setup was designed and manufactured to generate experimental data for the validation of numerical results. For experimentation, thin plate was vibrated with the help of string and servo motor, while acceleration of the plate was measured by accelerometer. Average acceleration of plate was measured by varying the rotational speed of motor. Frequency of the motor corresponding to maximum acceleration is known as fundamental natural frequency, which is equal to 1.42g in present case. Numerically calculated fundamental natural frequency of thin plate is 99.68 Hz. Numerical data fits well with experimental data as maximum percentage difference is 0.8%. Furthermore, results were also compared with the theoretical data available in literature, and found in excellent agreement as maximum percentage difference is less than 1%. At the end, experimentally obtained first mode shape was compared with the numerical one.