The analytical calculation of the problem are explained in this PDF document. These passages are taken from the isotropic analysis section of "Design, Analysis and Testing of a Formula SAE Carbon Fiber Monocoque Chassis" by Jingsi Wu, Owusu A. Agyeman Badu, and Yongcheng Tai.
Open ANSYS Workbench by going to Start > All Programs > ANSYS 14.0 > Workbench 14.0. This will open the start up screen as seen below:
Name the project: Modal Analysis of a Composite Monocoque.
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