Impact of Boundary Conditions and Radius of Curvature on Vibro-Acoustic Behavior of Cold-Rolled Carbon Steel Structure

The Cold-Rolled Carbon (CRC) steel is a widely used material for automobile, aerospace and machinery applications where the radius of curvature plays a vital role in their vibrational characteristics. Therefore, by identifying the factors that influence structural integrity and acoustic emissions, engineers can tailor designs to enhance performance and efficiency of those structures.

Hence, this study investigates the relationship between boundary conditions and the radius of curvature in shaping the vibro-acoustic behavior of CRC shell structures. The 3D solid structures at different radius of curvatures R=1000mm, 1500mm, and 2000mm were created, then imported into ANSYS workbench to perform modal, harmonic response and harmonic acoustics analysis.

As a result, minimum sound power level (SWL) was noticed from shell structures with a smaller radius of curvature (R=1000mm) while the excitation frequency was less than 500Hz. However, at higher frequency ranges (from 500Hz to 2000Hz), the shells with 1500mm and 2000mm curvature radius performed better in terms of SWL. Specifically, one side fixed 2000mm radius CRC shell structure produced the lowest far-field mic noise of 73.219dB, which is 7.5% less than the noise recorded at all side fixed condition for the same structure.

Hence, this study recommends smaller curvature radius (R=1000mm) for shell structures working under excitation frequency less than 500Hz for an effective vibration and noise control. Otherwise, higher curvature radius (i.e) above 2000mm is recommended if the excitation frequency range exceeds 500Hz.