Nonlinear aerodynamic stability of graphene-reinforced cars roof under aerodynamic pressures

The research investigates how automotive roof panels, which use graphene nanoplatelet (GPL) reinforcement, maintain their structural integrity during nonlinear aerodynamic assessments and their capability to transmit sound through supersonic wind tests. The roof structure is modeled as a doubly curved panel which uses two curvature factors to create an authentic representation of advanced vehicle design geometry. Various distributions of the GPLs along the thickness of materials are evaluated in this study to see their impact on aeroelastic stability as well as dynamic performance. The advanced structural kinematics are explained through a refined sinusoidal shear deformation theory which includes a nonlinear shear function to replace shear correction factors. The analysis includes geometric nonlinearities which develop when materials undergo moderate to large deflections and applies von Kármán strain-displacement relations. The researchers used Hamilton's principle to derive the coupled governing equations while first-order piston theory provided an unsteady aerodynamic loading model suitable for high Mach number flows.The panel's interaction with its supporting medium is simulated through a viscoelastic foundation which models both the torsional elastic layer energy input and the frictional resistance components. The displacement field solution uses a harmonic representation together with an iterative method to solve the resulting nonlinear equations. The method evaluates nonlinear dispersion relations which allow for the determination of both group and phase velocities. The results show that GPL distribution patterns and curvature parameters together with foundation properties determine the aerodynamic stability boundaries while they affect wave propagation patterns. The findings deliver essential information which designers need to create lightweight high-performance automotive structures that withstand extreme aerodynamic conditions.