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    Active flutter control of thin walled wing-engine system using piezoelectric actuators
    (Elsevier France-Editions Scientifiques Medicales Elsevier, 2020) Asadi, Davood; Farsadi, Touraj
    In the present study, control of a Thin Walled Beam (TWB) wing-engine system is examined applying piezoelectric actuators to enhance the performance of aeroelastic response. The composite piezoelectric governing equations of motion including the structure and electric effects are derived applying Hamilton's principle. Piezoelectric composite plate equations are added to the composite host wing-engine governing system of equations. The incompressible aerodynamic model based on Wagner's function is applied and the Ritz based solution methodology is employed. As a passive control approach, the effects of piezoelectric fiber angles are studied on the time domain response of the high-aspect-ratio wing-engine system. The linear quadratic Gaussian (LQG) control algorithm is applied as a closed-loop active control strategy to enhance the flutter response characteristics of the composite wing-engine system. Numerical results firstly, demonstrate the effectiveness of the active control strategy based on piezocomposite actuator on suppressing the flutter response of the composite wing-engine system and secondly, prove the effect of piezocomposite actuator location and fiber angle orientation on the closed-loop control performance. (C) 2020 Elsevier Masson SAS. All rights reserved.
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    Classical flutter analysis of composite wind turbine blades including compressibility
    (Wiley, 2021) Farsadi, Touraj; Kayran, Altan
    For wind turbine blades with the increased slenderness ratio, flutter instability may occur at lower wind and rotational speeds. For long blades, at the flutter condition, relative velocities at blade sections away from the hub center are usually in the subsonic compressible range. In this study, for the first time for composite wind turbine blades, a frequency domain classical flutter analysis methodology has been presented including the compressibility effect only for the outboard blade sections, which are in the compressible flow regime exceeding Mach 0.3. Flutter analyses have been performed for the baseline blade designed for the 5-MW wind turbine of NREL. Beam-blade model has been generated by making analogy with the structural model of the prewisted rotating thin-walled beam (TWB) and variational asymptotic beam section (VABS) method has been utilized for the calculation of the sectional properties of the blade. To investigate the compressibility effect on the flutter characteristics of the blade, frequency and time domain aeroelastic analyses have been conducted by utilizing unsteady aerodynamics via incompressible and compressible indicial functions. This study shows that with use of compressible indicial functions, the effect of compressibility can be taken into account effectively in the frequency domain aeroelastic stability analysis of long blades whose outboard sections are inevitably in the compressible flow regime at the onset of flutter.
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    COMPARATIVE STUDY OF FUNCTIONALLY GRADED MATERIAL MODELS FOR STRUCTURAL DESIGN OF THIN-WALLED BLADES
    (2021) Farsadi, Touraj
    In this work, three theories of Functionally Graded Material (FGM) are compared for structural dynamic and static performance \rof the thin-walled rotating blade. For this purpose, the pretwisted Thin Wall Rotating Beam (TWRB) with a fixed angular \rvelocity is considered. The goal is to find the desirable FG model with improved free vibration, static deformation, and buckling \rbehavior of the FGM blades. The Euler–Lagrange equations of motion of the energetic system are extracted utilizing Hamilton's \rprinciple. The Extended Galerkin`s Method (EGM) is used to solve the governing equation of motions. The effects of some \rparameters, such as the FGM models, angular velocity, and pretwist angle on the mechanical behavior of the FG beams are \rstudied.
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    Enhancement of Static and Dynamic Performance of Composite Tapered Pretwisted Rotating Blade With Variable Stiffness
    (Asme, 2021) Farsadi, Touraj
    Composite pretwisted tapered rotating thin-walled beams (TWB) can be used as a load-carrying structural part of a composite helicopter, wind turbine, fan, and turbomachinery blades. In the present study, the variable stiffness concept with curvilinear fiber path is used to achieve improved structural statics and dynamics performance of uniform and asymmetric composite thin-walled rotating beams. A parametric study is performed to investigate the effect of different fiber paths on the structural performance metrics including frequency spacing, coupling factor, and critical buckling load. For this purpose, The Euler-Lagrange governing equations of the dynamic system are derived via Hamilton's principle. To solve the governing set of equations, the extended Galerkin's method (EGM) is employed. To validate the TWB model with curvilinear fibers, commercial finite element analysis tools abaqus is used. The author believes that the results presented here are likely to provide valuable information to the engineers involved in the design of advanced turbomachinery rotating blades using a variable stiffness concept with curvilinear fiber placement.
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    Enhancing gust load alleviation performance in an optimized composite wing using passive wingtip devices: Folding and Twist approaches
    (Elsevier France-Editions Scientifiques Medicales Elsevier, 2024) Ahmadi, Majid; Farsadi, Touraj; Khodaparast, Hamed Haddad
    This paper introduces an innovative numerical method for the design and optimization of high-aspect-ratio composite wings equipped with passive control systems, specifically, Folding WingTip (FWT) and Twist WingTip (TWT) devices. The aim is to enhance Gust Load Alleviation (GLA) performance in the baseline wing. Recent numerical studies have indicated that the inclusion of spring devices and wingtip modifications can offer additional benefits in alleviating gust loads during flight. The baseline wing is designed using a comprehensive multi-disciplinary optimization framework, taking into account aerostructural constraints and exploiting the anisotropic properties of composite materials. The proposed methodology integrates Finite Element (FE) software, an in-house Reduced Order Model (ROM) framework for nonlinear aeroelastic analyses, and Particle Swarm Optimization (PSO). This method, implemented in the Nonlinear Aeroelastic Simulation Software (NAS2) package, facilitated the streamlined design of composite wings with optimized aeroelastic and structural performance. The paper is divided into two main parts. Part 1 introduces a Multidisciplinary Design Optimization (MDO) approach for high-aspect-ratio composite wings, leading to the development of a baseline wing model. Part 2 evaluates the effectiveness of the FWT and TWT devices in alleviating gust loads on the baseline wing, with a focus on the Root Bending Moment (RBM) as a critical criterion for comparison. In wingtip modeling, geometrical nonlinearity is incorporated, and elastic trim is adjusted in each iteration to accommodate shape changes under load and aerodynamic panel movement is synchronized with structural adjustments.
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    Flutter improvement of a thin walled wing-engine system by applying curvilinear fiber path
    (Elsevier France-Editions Scientifiques Medicales Elsevier, 2019) Farsadi, Touraj; Asadi, Davood; Kurtaran, Hasan
    In the present study, the aeroelastic behavior of a wing-engine system modeled as composite Thin Walled Beam (TWB) with curvilinear fiber path is investigated. The variable stiffness is acquired by constructing laminates of TWB with curvilinear fibers having prescribed paths. In order to account the effect of chordwise and spanwise locations, mass, and thrust force of engine on the aeroelastic characteristics of TWB, the novel governing equations of motion are obtained using Hamilton's variational principle. The paper aims to exploit desirable fiber paths with improved aeroelastic properties for different wing-engine configuration. Ritz based solution methodology is employed to solve the equations with coupled incompressible unsteady aerodynamic model based on Wagner's function. Numerical simulation results which conform to previously published literatures are presented for validation purposes. Although different curvilinear fiber paths can be introduced to enhance flutter instabilities for each wing-engine configurations, there exists an ideal placement of engine on the wing considering only the engine mass, and the engine mass and thrust force, simultaneously. A comprehensive insight is provided over the effect of parameters such as the lamination fiber path and the effect of engine positions with different mass and thrust values on the flutter speed and frequency. (C) 2019 Elsevier Masson SAS. All rights reserved.
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    Flutter Optimization of a Wing-Engine System with Passive and Active Control Approaches
    (Amer Inst Aeronautics Astronautics, 2021) Asadi, Davood; Farsadi, Touraj; Kayran, Altan
    In the present study, the flutter performance of a composite thin-walled beam wing-engine system is optimized by implementing two different control approaches: 1) passive open-loop and 2) active closed-loop control. Sequential quadratic programming and genetic algorithm methods are applied in the optimization process. In the passive control method, variable stiffness is acquired by constructing laminates of thin-walled beam with curvilinear fibers having prescribed paths. The goal is to exploit the desirable fiber paths with improved flutter performance to determine an optimized wing-engine aeroelastic configuration. In the active control strategy, piezo-composite actuators and the linear quadratic Gaussian algorithm are used to improve the flutter characteristics. A novel optimization strategy based on the total energy of the aeroelastic system is introduced and applied in both passive and active control strategies. The minimum total aeroelastic energy is an indication of ideal optimization variables, which leads to optimum flutter performance. The governing equations are formulated based on Librescu's thin-walled beam theory and Hamilton's principle. An unsteady aerodynamic model based on incompressible indicial aerodynamics is applied. The governing equations of motion are solved using a Ritz-based solution methodology. Numerical results demonstrate a 16 and 46% improvement in the flutter speed of the wing-engine system using the proposed passive and active control approaches, respectively. The presented results provide valuable information concerning the design of advanced lightweight and high-aspect-ratio aircraft wings with mounted engines in terms of favorable aeroelastic performance characteristics.
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    Flutter study of flapwise bend-twist coupled composite wind turbine blades
    (Techno-Press, 2021) Farsadi, Touraj; Kayran, Altan
    Bending-twisting coupling induced in big composite wind turbine blades is one of the passive control mechanisms which is exploited to mitigate loads incurred due to deformation of the blades. In the present study, flutter characteristics of bend-twist coupled blades, designed for load alleviation in wind turbine systems, are investigated by time-domain analysis. For this purpose, a baseline full GFRP blade, a bend-twist coupled full GFRP blade, and a hybrid GFRP and CFRP bend-twist coupled blade is designed for load reduction purpose for a 5 MW wind turbine model that is set up in the wind turbine multi -body dynamic code PHATAS. For the study of flutter characteristics of the blades, an over-speed analysis of the wind turbine system is performed without using any blade control and applying slowly increasing wind velocity. A detailed procedure of obtaining the flutter wind and rotational speeds from the time responses of the rotational speed of the rotor, flapwise and torsional deformation of the blade tip, and angle of attack and lift coefficient of the tip section of the blade is explained. Results show that flutter wind and rotational speeds of bend-twist coupled blades are lower than the flutter wind and rotational speeds of the baseline blade mainly due to the kinematic coupling between the bending and torsional deformation in bend-twist coupled blades.
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    Free vibration of three-layer sandwich plate with viscoelastic core modelled with fractional theory
    (Pergamon-Elsevier Science Ltd, 2021) Permoon, Mohammad R.; Farsadi, Touraj
    In the present study, natural frequencies and damping behavior of three-layer sandwich plates with viscoelastic core modelled with fractional theory are studied. Governing equations of motion are derived using Lagrange's equation and then solved via Rayleigh-Ritz method. In the first section of the analysis, the coefficients of the fractional and classical viscoelastic models are determined utilizing the curve fitting method on existed experimental data in the literature, and the best viscoelastic model is selected for free vibration analysis of sandwich plate. The method of least squares for fitting smooth curves to experimental data is applied. The results show that the fractional Zener model gives the best fit curve to the experimental data. After that, the effects of some geometrical parameters such as length to width ratio and viscoelastic core thickness on the natural frequency and loss factor of the sandwich plate with viscoelastic core are investigated, and some conclusions are drawn.
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    Fundamental Frequency Optimization of Doubly Curved Aerospace Structural Panels via Variable Stiffness Concept
    (2020) Farsadi, Touraj; Kurtaran, Hasan
    The fundamental natural frequencies of curvilinear fiber composite doubly curved panels are optimized. Doubly curved panels are used in numerous components of the structural frames of aerospace vehicles. The variable stiffness performanceis achieved by changing the fiber path to the curvilinear fiber path function in the composite structures. The structural model is developed based on the virtual work rule. The target is to attain the best fiber paths with maximum fundamental frequencies. An eight-layer composite doubly curved panel with two forms of boundary conditions is considered as anexample in this research. The boundary conditions include; CCCC, FCFC. Von-Karman kinematic strain relations are utilized and the FSDT is used to generalize the equation for the doubly curved panel. Generalized Differential Quadrature (GDQ) theory of solution is applied to solve the differential governing equations of motion. Numerical results reveal the efficiency of the curvilinear fiber path concept on the frequencies of the doubly curved panel. The optimum fiber path function of each layer is offered for the free vibration study.
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    Fundamental frequency optimization of variable stiffness composite skew plates
    (Springer Wien, 2021) Farsadi, Touraj; Asadi, Davood; Kurtaran, Hasan
    In this study, natural frequencies and vibrational mode shapes of variable stiffness composite skewed plates are optimized applying a genetic algorithm. The variable stiffness behavior is obtained by altering the fiber angles continuously according to two selected curvilinear fiber path functions in the composite laminates. Fundamental frequency and related mode shapes of the plates are optimized for two different fiber path functions using the structural model obtained based on the virtual work principle. A three-layer composite skewed plate with four types of boundary conditions and different plate geometries is considered as case study in this research. Diverse sweptback angles as well as different aspect ratios are considered as various plate geometries. The present study aims to calculate the best fiber path with maximized fundamental frequency or in-plane strengths for a composite skewed plate. The generalized differential quadrature method of solution is employed to solve the governing equations of motion. Moreover, the linear kinematic strain assumptions are used, and the first-order shear deformation theory is employed to generalize the formulation for the case of moderately thick plates including transverse shear effects. Numerical results demonstrate the effect of the fiber angles, boundary conditions, and diverse geometries on the natural frequencies of the composite plate. The optimal fiber angles of each layer are presented for the above cases in free vibration analysis. It is verified that the application of optimized curvilinear fibers instead of the traditional straight fibers introduces a higher degree of flexibility, which can be used to adjust frequencies and mode shapes.
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    High Aspect Ratio Composite Wings: Geometrically Nonlinear Aeroelasticity, Multi-Disciplinary Design Optimization, Manufacturing, and Experimental Testing
    (Mdpi, 2024) Farsadi, Touraj; Ahmadi, Majid; Sahin, Melin; Khodaparast, Hamed Haddad; Kayran, Altan; Friswell, Michael I.
    In the field of aerospace engineering, the design and manufacturing of high aspect ratio composite wings has become a focal point of innovation and efficiency. These long, slender wings, constructed with advanced materials such as carbon fiber and employing efficient manufacturing methods such as vacuum bagging, hold the promise of significantly lighter aircraft, reduced fuel consumption, and enhanced overall performance. However, to fully realize these benefits, it is imperative to address a multitude of structural and aeroelastic constraints. This research presents a novel aeroelastically tailored Multi-objective, Multi-disciplinary Design Optimization (MMDO) approach that seamlessly integrates numerical optimization techniques to minimize weight and ensure structural integrity. The optimized wing configuration is then manufactured, and a Ground Vibration Test (GVT) and static deflection analysis using the Digital Image Correlation (DIC) system are used to validate and correlate with the numerical model. Within the fully automated in-house Nonlinear Aeroelastic Simulation Software (NAS2) package (version v1.0), the integration of analytical tools offers a robust numerical approach for enhancing aeroelastic and structural performance in the design of composite wings. Nonlinear aeroelastic analyses and tailoring are included, and a population-based stochastic optimization is used to determine the optimum design within NAS2. These analytical tools contribute to a comprehensive and efficient methodology for designing composite wings with improved aeroelastic and structural characteristics. This comprehensive methodology aims to produce composite wings that not only meet rigorous safety and performance standards but also drive cost-efficiency in the aerospace industry. Through this multidisciplinary approach, the authors seek to underscore the pivotal role of tailoring aeroelastic solutions in the advanced design and manufacturing of high aspect ratio composite wings, thereby contributing to the continued evolution of aerospace technology.
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    Improvement of structural characteristics of composite thin-walled beams using variable stiffness concept via curvilinear fiber placement
    (Sage Publications Ltd, 2021) Farsadi, Touraj; Bozkurt, Mirac Onur; Coker, Demirkan; Kayran, Altan
    This study presents the use of variable stiffness concept via curvilinear fiber placement to achieve improved structural characteristics in composite thin-walled beams (TWBs). The TWB used in the study is constructed in circumferentially asymmetric stiffness (CAS) configuration. The variation of fiber angles along the span and the width of the TWB is included by defining two fiber path functions. A parametric study is performed to investigate the effects of different fiber paths on the structural performance metrics including frequency spacing, unit twist, and critical buckling load. For this purpose, a semi-analytical solution method is developed to conduct free vibration, deformation, and buckling analyses of the TWB with curvilinear fibers. The semi-analytical method is validated with several finite element (FE) analyses performed using ABAQUS. Elastic stress analyses of TWBs with selected fiber paths subjected to simplified distributed loading are also conducted using the FE method, and a ply failure criterion is applied to evaluate the strength of these TWBs. Overall results show that curvilinear fiber placement varied along the span leads to greater structural performance for a composite TWB than the straight fiber configuration.
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    Linkage Learning Optimization of Aeroelastic and Structural Behavior of Composite Wings
    (Springer, 2023) Rafiee, Roham; Farsadi, Touraj; Tehrani, Majid Ahmadi; Sharifi, Parsa
    The paper aims to develop a systematic numerical design for composite wings optimization subject to aerodynamic loading and to assess the aeroelastic and structural performance of the optimized composite wing. Aeroelastic tailoring is a powerful method for utilizing the anisotropic features of composite materials used in lightweight aerospace structures. The present proposed methodology combines three different analysis tools: a commercial FE software commonly used in industry, an in-house reduced order aeroelastic framework for aeroelastic analyses with tailoring capabilities, LLGA, in-house linkage-learning genetic algorithms for optimization of stacking sequences. As a multidisciplinary problem where structural and aeroelastic behaviors are interacted, developed multi-level optimization scenario in this research converges to the optimal design in a very short time. The proposed methodology implemented as a computer code can effectively be applied to any arbitrary air vehicle's composite wing by changing input data.
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    Multidisciplinary optimization of high aspect ratio composite wings with geometrical nonlinearity and aeroelastic tailoring
    (Elsevier France-Editions Scientifiques Medicales Elsevier, 2024) Ahmadi, Majid; Farsadi, Touraj
    This study presents a systematic numerical approach for the design and optimization of high aspect ratio composite wings subjected to aerodynamic loads. The primary objective is to develop a multi-objective, multidisciplinary optimization framework that considers aerostructural constraints, such as subsonic aeroelasticity and geometrical nonlinearity. The incorporation of anisotropic properties of composite materials is emphasized to construct lightweight aerospace structures. Aeroelastic tailoring, a technique leveraging these properties, is employed in the optimization process. The proposed methodology integrates three analysis tools, Finite Element software for structural behavior simulation, an in-house Reduced Order Model (ROM) framework for nonlinear aeroelastic analyses with tailoring capabilities, and Particle Swarm Optimization (PSO) as a population-based stochastic optimization method. This integration enables the development of a powerful numerical approach, implemented in the Nonlinear Aeroelastic Simulation Software (NAS2) package, for designing composite wings with optimized aeroelastic and structural performance. The proposed methodology has broad applicability in aerospace engineering, encompassing aircraft and unmanned aerial vehicles, offering significant potential to enhance their design and overall performance.
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    Nonlinear analysis of functionally graded skewed and tapered wing-like plates including porosities: A bifurcation study
    (Elsevier Sci Ltd, 2021) Farsadi, Touraj; Rahmanian, Mohammad; Kurtaran, Hasan
    In the present study, nonlinear panel flutter and bifurcation behavior of functionally graded ceramic/metal winglike tapered and skewed plates are investigated. Porosities are distributed over the cross-section of the functionally graded structure. The flutter speed, limit cycle oscillations, and bifurcation diagrams of the functionally graded plate with two types of geometrical non-uniformities being skewness and taperness are explored. Nonlinear structural model is utilized based on the virtual work principle by including the von-Karman nonlinear kinematic strain assumption. The first order shear deformation theory is employed to consider the transverse shear effect in the structural model. First-order linear piston theory is used to model the aerodynamic loading while the generalized differential quadrature method is employed to solve the governing equations of motion. Time integration of the final ordinary equations of motion is carried out using the Newmark average acceleration method. Different volume fractions are investigated to enhance the flutter instability margins and post-flutter behavior of functionally graded plates. Results demonstrate that the volume fraction and porosity coefficients have significant effects on dynamic behavior and limit cycle oscillation amplitudes.
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    Nonlinear flutter of tapered and skewed cantilevered plates with curvilinear fiber paths
    (Academic Press Ltd- Elsevier Science Ltd, 2021) Rahmanian, Mohammad; Farsadi, Touraj; Kurtaran, Hasan
    Aeroelastic stability of tapered/skew variable stiffness composite cantilevered plates are considered in the current study at flutter and post-flutter regions. The variable stiffness behavior is obtained by altering the fiber angles continuously according to a selected curvilinear fiber path function in the composite laminates. Flutter speed, limit cycle oscillations (LCOs), and bifurcation diagrams of tapered/skewed plates are obtained at two different fiber path functions. Nonlinear structural model is utilized based on the virtual work principle. Fully nonlinear Green's kinematic strain relations are used to account for the geometric nonlinearities and the first order shear deformation theory (FSDT) is employed to generalize the formulation for the case of moderately thick plates including transverse shear effects. One prominent target of the present study is to determine how the variable stiffness parameters affect the nonlinear behavior. Consequently, one may find the best fiber path with improved flutter and post-flutter characteristics for tapered/skew plates in supersonic flow. First order linear piston theory is used to model the aerodynamic loading. In order to get a reliable solution, the Generalized Differential Quadrature (GDQ) method is employed. Moreover, time integration of the equations of motion is carried out using the Newmark's average acceleration technique. It will be shown that taperness/skewness as well as variable stiffness lamination parameters have significant effects on the aeroelastic stability margins. In addition, the post-critical behavior is found to be periodic or quasi-periodic at all the presented simulations with no specific route to chaos. (c) 2021 Elsevier Ltd. All rights reserved.
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    Nonlinear flutter response of a composite plate applying curvilinear fiber paths
    (Springer, 2020) Farsadi, Touraj; Asadi, Davood; Kurtaran, Hasan
    In the present study, nonlinear flutter and post-flutter behavior of a variable stiffness composite wing-like plate is investigated. The variable stiffness is obtained by varying fiber angles continuously according to a selected curvilinear fiber path function in the composite laminates. Flutter speed, limit cycle oscillations and bifurcation diagrams of the composite plate are explored for three different fiber path functions using the nonlinear structural model obtained based on the virtual work principle. The paper aims to exploit the ideal fiber paths with enhanced aeroelastic flutter and post-flutter properties for a composite plate in supersonic flow speed. First-order linear piston theory is applied to model the aerodynamics, and generalized differential quadrature is employed to solve the governing equations. Von Karman nonlinear strain theory is used to account for the geometric nonlinearities, and first-order shear deformation theory is employed to consider the transverse shear effects in the structural model. Time integration of the equation of motion is carried out using the Newmark average acceleration method. Different curvilinear fiber paths are introduced to enhance flutter instabilities and post-flutter behavior of the composite plate. Results demonstrate that the fiber orientation has a significant effect on the dynamic behavior of the plate and the asymmetric properties as well as the behavior of the limit cycle oscillation. © 2019, Springer-Verlag GmbH Austria, part of Springer Nature.
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    Nonlinear lay-up optimization of variable stiffness composite skew and taper cylindrical panels in free vibration
    (Elsevier Sci Ltd, 2021) Farsadi, Touraj; Rahmanian, Mohammad; Kurtaran, Hasan
    In the present study, the fundamental natural frequencies of curvilinear fiber composite skew and taper cylindrical panels are optimized applying genetic algorithm (GA). Later, the fundamental amplitude-dependent nonlinear frequency behavior of the optimized curved fiber layup configurations is studied and compared with the reference unidirectional fiber layup. The variable stiffness behavior is obtained by altering the fiber angles continuously according to the curvilinear fiber path function in the composite laminates. A nonlinear structural model is utilized based on the virtual work principle. Green?s nonlinear kinematic strain relations are used to account for the geometric nonlinearities and the first-order shear deformation theory (FSDT) is adopted to generalize the formulation for the case of moderately thick cylindrical panels including transverse shear deformations. The goal is to determine how the variable stiffness parameters affect the linear and nonlinear free vibration behavior of the skew and taper cylindrical panels. Consequently, one may find the optimum fiber path with improved structural characteristics for the cylindrical panel. Eight-layered composite skew and taper cylindrical panels at two different boundary condition sets are considered in this research. Generalized Differential Quadrature (GDQ) method of solution is employed to solve the nonlinear governing equations of motion. Numerical results demonstrate the degree of effectiveness for fiber angle paths, boundary conditions, and geometrical non-uniformities on the fundamental frequencies of the cylindrical panel. Eventually, optimum fiber angles of each layer in free vibration analysis are presented.
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    Nonlinear stability of multilayered graphene platelet-reinforced functionally graded wing-like plates
    (Springer Wien, 2022) Farsadi, Touraj; Rahmanian, Mohammad; Kurtaran, Hasan
    Nonlinear panel flutter and post-flutter behavior of wing-like, taper, and skew plates made of functionally graded (FG) multilayered graphene platelet-reinforced polymer composite (GPL-RPC) are investigated in this study. Using two types of geometrical non-uniformity, skew and taper, the flutter boundary, limit cycle oscillations, and bifurcation plots of functionally graded GPL-RPC plates are reported. The graphene platelet (GPL) nanofillers are assumed to be dispersed uniformly or non-uniformly in the matrix and in the thickness direction. All GPL distribution patterns of UD, FG-O, FG-X, and FG-A are considered. The modified Halpin-Tsai micro-mechanical model and the rule of mixture are utilized to determine the effective material characteristics of GPL-RPC layers. In order to obtain the nonlinear mathematical model for the non-uniform plates, Von-Karman kinematic strains descriptions are used along with the virtual work principle and Hamilton's expression. To generalize the structural model, a first-order shear deformation theory (FSDT) is used. The well-recognized first-order piston theory is also utilized to account for the aerodynamic loading description. In the end, governing differential equations of motion are projected to their equivalent algebraic representation by means of the generalized differential quadrature method (GDQM), which is then followed by a time integration using the Newmark's average acceleration scheme. The goal of current research is to find how the GPL weight fraction affects the flutter instability margins and post-flutter behavior for FG GPL-RPC cantilevered plates at several proposed distribution patterns.