This article discusses the challenge of defining the geometry parameters for minimum mass stiffened aircraft panels made of composite materials.The thickness and size of the panel elements are unknown variables,and th...This article discusses the challenge of defining the geometry parameters for minimum mass stiffened aircraft panels made of composite materials.The thickness and size of the panel elements are unknown variables,and the optimal design is based on the condition of equal buckling.To solve this problem,the authors reduce the optimal design problem to the investigation of the weight function with multiple variables using analytical methods and refined buckling theory restrictions.The article introduces novel mathematical relationships for investigating the buckling of structurally anisotropic composite panels.The model couples bending with a plane stress state,resulting in a boundary value problem that involves solving an eighth-order partial differential equation within a rectangular field.To facilitate this,a software package was developed using theMATLAB operating environment.A set of computer programs was created to conduct multi-criteria optimization of the optimal design of structurally anisotropic aircraft composite panels.The study also examines the impact of design parameters on the critical buckling forces for both bending and torsion modes.The results of a new implementation of an optimal size-weight project for carbon-epoxy skin are given.A project with restrictions on the refined buckling theory for structurally anisotropic aircraft panels made of composite materials has been manipulated in terms of plies thicknesses.Optimal solutions are obtained.展开更多
The results of fatigue strength estimates,required for ensuring durability design goal of composite materials made upper and lower panels of the prospective supersonic transport aircraft(PSTA)wing are presented.Develo...The results of fatigue strength estimates,required for ensuring durability design goal of composite materials made upper and lower panels of the prospective supersonic transport aircraft(PSTA)wing are presented.Developed estimates of the fatigue properties are based on the approximations gained from published sources.Fatigue strength(S–N)equations for composite panels of the PSTA wing are deduced,which might be followed by procedure of compliance to service design goal.The methods developed are used to compare intact and required fatigue strength of original carbon fiber reinforced plastic(CFRP)and one with modified properties by nanoparticles inclusion.Finally,the sensitivity of the developed fatigue strength estimates to chosen parameters is studied.Developed methodology can be utilized during preliminary strength analysis of the PSTA wing panels.展开更多
In this paper,the patterns of fatigue damage accumulation for a stringer panel and a panel with lattice reinforcement made of a polymer composite material(PCM)were studied using the Wim Van Paepegem calculation method...In this paper,the patterns of fatigue damage accumulation for a stringer panel and a panel with lattice reinforcement made of a polymer composite material(PCM)were studied using the Wim Van Paepegem calculation method.Both panels have the same overall dimensions,are made of the same material and are designed to carry the same compressive load.Based on the results of the calculations,the zones were determined in which the greatest loss of stiffness occurs in one of the components for both types of panels.The number of cycles to complete loss of stiffness for these components for each of the zones was obtained.It was found that in the stringer panel,the greatest loss of stiffness occurs in the layers of the stringer web and in the panel with lattice reinforcement in the zone where the diagonal ribs intersect.At the same time,it was found that in a lattice panel,these fatigue damage occurs under a smaller number of applied cycles than in a stringer panel.展开更多
基金the implementation of the program for the creation and development of the World-Class Research Center“Supersonic”for 2020-2025 funded by the Ministry of Science and Higher Education of the Russian Federation(Grant agreement of April 20,2022№075-15-2022-309).
文摘This article discusses the challenge of defining the geometry parameters for minimum mass stiffened aircraft panels made of composite materials.The thickness and size of the panel elements are unknown variables,and the optimal design is based on the condition of equal buckling.To solve this problem,the authors reduce the optimal design problem to the investigation of the weight function with multiple variables using analytical methods and refined buckling theory restrictions.The article introduces novel mathematical relationships for investigating the buckling of structurally anisotropic composite panels.The model couples bending with a plane stress state,resulting in a boundary value problem that involves solving an eighth-order partial differential equation within a rectangular field.To facilitate this,a software package was developed using theMATLAB operating environment.A set of computer programs was created to conduct multi-criteria optimization of the optimal design of structurally anisotropic aircraft composite panels.The study also examines the impact of design parameters on the critical buckling forces for both bending and torsion modes.The results of a new implementation of an optimal size-weight project for carbon-epoxy skin are given.A project with restrictions on the refined buckling theory for structurally anisotropic aircraft panels made of composite materials has been manipulated in terms of plies thicknesses.Optimal solutions are obtained.
基金the program for the creation and development of the World-Class Research Center“Supersonic”for 2020–2025 funded by the Ministry of Science and Higher Education of the Russian Federation(Grant agreement of April,20,2022№075-15-2022-309).
文摘The results of fatigue strength estimates,required for ensuring durability design goal of composite materials made upper and lower panels of the prospective supersonic transport aircraft(PSTA)wing are presented.Developed estimates of the fatigue properties are based on the approximations gained from published sources.Fatigue strength(S–N)equations for composite panels of the PSTA wing are deduced,which might be followed by procedure of compliance to service design goal.The methods developed are used to compare intact and required fatigue strength of original carbon fiber reinforced plastic(CFRP)and one with modified properties by nanoparticles inclusion.Finally,the sensitivity of the developed fatigue strength estimates to chosen parameters is studied.Developed methodology can be utilized during preliminary strength analysis of the PSTA wing panels.
基金the program for the creation and development of the World-Class Research Center“Supersonic”for 2020-2025 funded by the Ministry of Science and Higher Education of the Russian Federation(Grant agreement of April,20,2022№075-15-2022-309).
文摘In this paper,the patterns of fatigue damage accumulation for a stringer panel and a panel with lattice reinforcement made of a polymer composite material(PCM)were studied using the Wim Van Paepegem calculation method.Both panels have the same overall dimensions,are made of the same material and are designed to carry the same compressive load.Based on the results of the calculations,the zones were determined in which the greatest loss of stiffness occurs in one of the components for both types of panels.The number of cycles to complete loss of stiffness for these components for each of the zones was obtained.It was found that in the stringer panel,the greatest loss of stiffness occurs in the layers of the stringer web and in the panel with lattice reinforcement in the zone where the diagonal ribs intersect.At the same time,it was found that in a lattice panel,these fatigue damage occurs under a smaller number of applied cycles than in a stringer panel.
