Shahrood University of Technology Journal of Solid and Fluid Mechanics 2251-9475 12 2 2022 05 22 Detection of Single and Multiple Cracks in Circular Cylindrical Shells Using Modal Analysis and Wavelet Transform Detection of Single and Multiple Cracks in Circular Cylindrical Shells Using Modal Analysis and Wavelet Transform 13 28 2484 10.22044/jsfm.2022.6205.2473 FA Sh. Samimian Tehrani Department of Mechanical Engineering, Shahid Beheshti University, Tehran, Iran P. Safarpour Beheshti University M. Babaei Lecturer, Faculty of Mechanical Engineering, University of Eyvanekey F. Kiarasi Lecturer, Faculty of Mechanical Engineering, University of Eyvanekey Journal Article 2017 09 09 In this paper, a method is studied for detecting single and multiple cracks in the thin and thick-walled Circular cylindrical shell based on the modal analysis and wavelet transform without using baseline modal data. In this research, the studied crack is the type of circumference and all over and it is also modeled in the form of hairline and without width by the ABAQUS software. The mode shapes of two thin and thick-walled cylindrical shells are obtained with free-free and simple-simple support conditions and with different cracks ratio. The cracked sample response is moved to static wavelet transform toolbox in the MATLAB software. Then, the noise signal is obtained by assuming crack as noise and removing noise at the first decomposition level of the input signal and. Finally, after reviewing 3240 various modes, the best wavelets are introduced to accurate detection of the cracks up to 2% crack ratio and without displaying the support effects. In this paper, a method is studied for detecting single and multiple cracks in the thin and thick-walled Circular cylindrical shell based on the modal analysis and wavelet transform without using baseline modal data. In this research, the studied crack is the type of circumference and all over and it is also modeled in the form of hairline and without width by the ABAQUS software. The mode shapes of two thin and thick-walled cylindrical shells are obtained with free-free and simple-simple support conditions and with different cracks ratio. The cracked sample response is moved to static wavelet transform toolbox in the MATLAB software. Then, the noise signal is obtained by assuming crack as noise and removing noise at the first decomposition level of the input signal and. Finally, after reviewing 3240 various modes, the best wavelets are introduced to accurate detection of the cracks up to 2% crack ratio and without displaying the support effects. https://jsfm.shahroodut.ac.ir/article_2484_72cb2edd4795359d888819c60e036d10.pdf