A method for nonlinear aeroelasticity trim and stability analysis of very flexible aircraft based on co-rotational theory

Wang, Wei; Zhu, Xiaoping; Zhou, Zhou; Duan, Jingbo

doi:10.1016/j.jfluidstructs.2016.01.009

Cited by 9 publications

(3 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To account for computational efficiency, the CR method has been developed. Currently, to conduct aeroelastic analyses of HARW, many researchers have developed nonlinear spar [24,25], rod [26], and shell [27][28][29][30] elements using the CR method. Kirsch et al [31] also developed a calculation program specifically for the aeroelastic analysis of flexible aircraft.…”

Section: Introductionmentioning

confidence: 99%

Effect of Stiffness on Flutter of Composite Wings with High Aspect Ratio

Qiao

Jiao

et al. 2021

Mathematical Problems in Engineering

View full text Add to dashboard Cite

High aspect ratio wing (HARW) structures will deform greatly under aerodynamic loads, and changes in the stiffness will have a great impact on the flutter characteristics of such wings. Based on this, this paper presents an effective method to determine the effect of the stiffness on the flutter characteristics of HARWs. Based on the calculation theory of the mechanical profile of thin-walled structures, the torsional stiffness and bending stiffness of the wing are obtained through calculation. We use the fluid-structure coupling method to analyze the flutter characteristics of the wing, and we use our research results based on the corotational (CR) method to perform structural calculations. The load is calculated using a computational fluid dynamics (CFD) solver. The results show that, compared with the original wing, when the bending stiffness and torsional stiffness of the wing along the spanwise direction increase by 8.28% and 5.22%, respectively, the amplitude of the flutter decreases by approximately 30%. Increasing the stiffness in the range of 0.4 to 0.6 Mach has a greater impact on the flutter critical velocity, which increases by 12.03%. The greater the aircraft’s flight speed is, the more severe the stiffness affects the wing limit cycle oscillation (LCO) amplitude.

show abstract

Section: Introductionmentioning

confidence: 99%

Effect of Stiffness on Flutter of Composite Wings with High Aspect Ratio

Qiao

Jiao

et al. 2021

Mathematical Problems in Engineering

View full text Add to dashboard Cite

show abstract

“…In the past several years, many scholars have carried out many studies on large-scale flexible aircraft, including nonlinear aeroelastics [5]- [8], coupling dynamics modeling [9], [10], model reduction [11], [12], stability analysis [13], [14], trajectory tracking [1], [15], flutter suppression and gust alleviation [16]- [18]. These studies strongly promote investigations of the dynamic characteristics of highly flexible aircraft.…”

Section: Introductionmentioning

confidence: 99%

A Study on Stability Boundary of Highly Flexible Aircraft With Saturation Constraint

Cao

Liu

et al. 2021

IEEE Access

View full text Add to dashboard Cite

This paper deals with investigating the closed-loop stability boundary of the highly flexible aircraft with structural flexibility and input saturation constraint. A method is presented to analyze the stable region based on the system features of the open-loop instability. In this paper, a dynamic model of highly flexible aircraft is made and the dynamic characteristics are analyzed and the long period mode and stability are investigated in terms of the trimmed model. Considering the saturation constraint of elevator deflection, the closed-loop stability boundary of the system under saturation constraint is discussed by combining the open-loop instability features of highly flexible aircraft. The analysis indicates that the boundary is related to the left eigenvector consistent with the amplitude constraint and the unstable poles of the control signals. Based on the long period instability of the aircraft, the formula of closed-loop stability boundary is analytically obtained. The convergence region of highly flexible aircraft is verified in terms of the LQR controller. The influence of structural flexibility and saturation constraint amplitude of elevator on the stability boundary of highly flexible aircraft is analyzed based on state constraints, which is also compared with the rigid aircraft. The simulation results show that the closed-loop stability of the system is restricted by the open-loop characteristic of the system and the control input saturation constraint.

show abstract

“…As a result, the wing becomes flexible and results in large deformation even during normal flight. 3,4 Various studies have been carried out for highly flexible aircraft which is summarized here, such as nonlinear coupling dynamics modeling and reduction, [5][6][7] stability analysis, 8,9 structural optimization, 10,11 flutter suppression, and gust alleviation etc. 12,13 According to the analysis of large-scale flexible aircraft model, their results suggest that the main problems in the design of control system are to ensure the stability of the aircraft's closed-loop system, under the condition of saturation, and bandwidth constraints.…”

Section: Introductionmentioning

confidence: 99%

Stability boundary analysis of highly flexible aircraft with control saturation and structural flexibility

Chen

et al. 2020

Proceedings of the Institution of Mechanical Engineers, Part G:

View full text Add to dashboard Cite

In this work, a method has been presented to analyze the influence of control saturation and structural flexibility on the stable radius of highly flexible aircraft. A dynamic model of aircraft is constructed followed by the analysis of kinetic characteristics. In this paper, the closed-loop stability boundary of highly flexible aircraft with open-loop instability is studied. The amplitude limit and bandwidth limit of the control signal are considered in the closed-loop stability boundary calculation. Our analysis shows that the boundary is related to the left eigenvector corresponding to the unstable poles and the amplitude constraint of the control signals. Stability of the boundary of feedback control system further reduces the limitation of the bandwidth of actuators. Focused on the phugoid instability of highly flexible aircraft, computational formulation of the closed-loop stable boundary is achieved. The Monte Carlo analysis has been employed to validate the stable region, under the LQR controller. Both the theory and simulations have nice correlations with each other which verify the stability of the closed-loop system, restricted by the open-loop system, and the influence of control signal bandwidth constraints.

show abstract

A method for nonlinear aeroelasticity trim and stability analysis of very flexible aircraft based on co-rotational theory

Cited by 9 publications

References 21 publications

Effect of Stiffness on Flutter of Composite Wings with High Aspect Ratio

Effect of Stiffness on Flutter of Composite Wings with High Aspect Ratio

A Study on Stability Boundary of Highly Flexible Aircraft With Saturation Constraint

Stability boundary analysis of highly flexible aircraft with control saturation and structural flexibility

Contact Info

Product

Resources

About