Vibroacoustic parametric analysis of honeycomb composite fuselage for improved transmission loss

Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering"December 2007."Much research has been done on reducing the noise level within a honeycomb composite fuselage used in aircraft. The honeycomb composite fuselage has shown much promise for structural rigidity, but to reduce cabin noise, transmission loss and radiation efficiency of the honeycomb fuselage must be taken into consideration in the initial design stage. This thesis is a parametric study of a honeycomb composite fuselage for improving the acoustical performance by reducing transmission loss through the panel. Various models of honeycomb composite were modeled using HyperMesh, a modeling software. The structural model was validated statically with four-point bend-test data and by means of modal analysis, by correlation of composite panel analytical results to published benchmark results. The composite panel model was also validated by correlating the panel transmission loss results using vibroacoustic analysis using VA One software to the published benchmark results. Physical parameters, including length and thickness of the honeycomb panels, were varied and modeled. Geometric properties such as length, thickness, and material properties including Young’s modulus and shear modulus were selected for the validated model. A parametric study was then done to find an improved transmission loss by varying the core thickness, core cell size and core density, and by adding plies, limp material and noise-control treatments