Optimization of Vibro-Acoustic Characteristics of Cold Rolled Sandwich Steel Cylindrical Shell with Internal Voids Using Response Surface Methodology

Mechanical vibration is a problem in aerospace, mechanical, and civil systems. Adverse aerodynamic circumstances, including generated random vibrations, may occur in vehicle and aerospace designs, where the components are largely in the form of curved/flat/thin walled shell structures. Active vibration control is thus essential to improve the performance and durability of the structures. This study proposes an experimental and statistical investigation of the vibro-acoustic behaviour of three layered cold rolled coil (CRC) steel cylindrical shell structures with and without internal voids in the central layer. The axial mode of vibration through the impact hammer is experienced by the circular cylindrical shells that are made with three distinct radiuses of curvature: 1000, 1500, and 2000 mm. Four boundary conditions are used for the vibration research of the manufactured shell structures: free placed, one side fixed, two side fixed, and all side fixed. Through the use of response surface methodology (RSM), the modal frequencies and modal spectrums of the cylindrical thin shells are examined experimentally and theoretically validated. Face-centered central composite design (FCCD) is used in the RSM to carry out the multi-objective optimization of the experiment. The RSM-FCCD models’ optimized design parameters, which produced 15.39 Hz of vibration and 44.01 dB of noise, were 2000 mm curvature radius, 1.5 mm voids, and one side fixed condition.