Response Of Aircraft Wing Research Articles

Design and Analysis of Fluid Structure Interaction in a Horizontal Micro Channel

This paper demonstrates techniques for modelling fluid-structure interactions using COMSOL Multiphysics v 4.2a, which illustrates how to solve for the flow in a continuously deforming geometry using the Arbitrary Lagrangian-Eulerian (ALE) technique and corresponding deformation, displacement analysis. The present work reports the computation of the deformation and displacement in structure along with the fluid flow in a continuously deforming geometry, for different types of structures like circular, rectangular, ellipse, which are placed inside of the flow channel as an obstacle. Fluid structure interaction between wind and sails, modelling of parachutes, fluid structure thermal calculation, stability and response of aircraft wings, the flow of blood through arteries, response of bridges and tall buildings to winds, prediction of aero elastic parameters in military aircrafts, vibration of turbine and compressor blades and the oscillation of heat exchangers can also be analysed using this method

Adaptive Control of Aircraft Wing Flutter by Stress-Induced Stiffness Modification

Lightweight unoccupied air vehicles (UAVs) with wide wingspans are especially vulnerable to dynamic instability. Such instability can be contained by using mass and stiffness balancing and the shape and attitude of the aircraft in flight. Passive methods and pilot-operated devices such as dampers, ailerons, flaps, and other actuators, are currently used. Also, ongoing attempts exist to develop self-adaptive controls by using piezoelectric and other devices. The present work is concerned with controlling aerodynamic flutter by using stress-induced elements in selected structural components of the aircraft wing. A scheme has been developed to determine the “optimal” locations for such elements to be activated, in real time, to contain the dynamic instability or flutter condition. Various stress-induced stiffening schemes have been developed to modify the frequency response of aircraft wings by shifting the critical flutter speed to safe levels. Results and conclusions include the identification of the optimal location and type of the stress-induced elements and the magnitude and distribution of induced stress for best results with the least expense of energy during actuation.

MODELING OF FLUID-STRUCTURE INTERACTION

▪ Abstract The interaction of a flexible structure with a flowing fluid in which it is submersed or by which it is surrounded gives rise to a rich variety of physical phenomena with applications in many fields of engineering, for example, the stability and response of aircraft wings, the flow of blood through arteries, the response of bridges and tall buildings to winds, the vibration of turbine and compressor blades, and the oscillation of heat exchangers. To understand these phenomena we need to model both the structure and the fluid. However, in keeping with the overall theme of this volume, the emphasis here is on the fluid models. Also, the applications are largely drawn from aerospace engineering although the methods and fundamental physical phenomena have much wider applications. In the present article, we emphasize recent developments and future challenges. To provide a context for these, the article begins with a description of the various physical models for a fluid undergoing time-dependent motion, then moves to a discussion of the distinction between linear and nonlinear models, time-linearized models and their solution in either the time or frequency domains, and various methods for treating nonlinear models, including time marching, harmonic balance, and systems identification. We conclude with an extended treatment of the modal character of time-dependent flows and the construction of reduced-order models based on an expansion in terms of fluid modes. The emphasis is on the enhanced physical understanding and dramatic reductions in computational cost made possible by reduced-order models, time linearization, and methodologies drawn from dynamical system theory.