Pet Containment Systems Rf-1002

Aeroelasticity and aeroelastic phenomena. SAE

contours and flow lines Mach, for aeroelastic simulation at Mach 0.9
The color indicates the local variation of the Mach number (increasing from blue to red) on the surface of the aircraft.

Caracas, 07/08/2010, Aeroblog .- The Aeroelasticity is the science from which studies the interaction of inertial, elastic, and aerodynamic forces. Was defined in 1947 as Collar "the study of the mutual forces of interaction that occurs within the triangle of inertia, elastic, and aerodynamic acting on structural members exposed to an airstream, and the influence of study design .
Aeroelasticity is the discipline of aeronautical engineering that studies the response of flexible fuel vehicles subject to aerodynamic and external actions in the case of aircraft, requires the coupling of forces inertial, structural, aerodynamic and control laws (aeroservoelasticity). The classical approach considers linear models, which can not be true under certain conditions: structural nonlinearities freeplay or the rotation of the control surfaces, movement of fuel in the tanks (fuel sloshing) in maneuvers with high load factors high performance aircraft, current release, transonic flow or laws of nonlinear flight dependent on flight condition or maneuver.

Aeroelasticity is a core that is based on three pillars: the mechanics of solids (material resistance), mechanics and fluid dynamics. Studying an aeroelastic phenomenon involves analyzing the interaction between structural deformation of the structure and aerodynamic loads depend on it. Modern structures of aircraft are not completely rigid and aeroelastic phenomenon occurs when the structural deformations induce changes in aerodynamic forces. Additional aerodynamic forces involve an increase in structural deformation, which in turn leads to greater aerodynamic forces. These interactions can gradually become smaller until reaching an equilibrium, or they can diverge catastrophically.

Aeroelasticity can be divided into two fields of study: static aeroelasticity (divergence and reversal command) and dynamic (flutter, and buffeting dynamic response).

Static Aeroelasticity Aeroelasticity static

addresses the interaction between elastic and aerodynamic forces without considering the properties of dough. The existence of large deformation is not necessarily a problem but they have to be considered during the design process so as to ensure the smooth operation of the aircraft. Within the static aeroelasticity are:

Divergence. Is a static aeroelastic instability that can lead to structural failure. It is caused by the fact that the aerodynamic forces exceed the elastic forces of the structure. Subjected to aerodynamic loads, the aircraft structure is deformed so that the aerodynamic loads increase. Upon reaching a critical speed of the aircraft with the wind, self-powered strain can conclude in structural failure.

reduced efficiency of the control surfaces or investment control. The reduction in the efficiency of the control surfaces at high speed caused by structural distortions is one of the biggest problems for the aircraft. The stability properties and control of the aircraft depend heavily on the aerodynamic load distribution.

rising to a surface (such as the wing or the tail), the central problem is the effect of deformation. A small flight speeds, the distortions are minimal and pose no real danger, however, at speeds large, the effect of these deformations can become so serious to the extent of causing instability of the wing, control surface again ineffective and even reverse the controls.

Dynamic Aeroelasticity Aeroelasticity dynamic studies the interaction between aerodynamic forces, elastic and inertial. Within the concept of dynamic aeroelasticity, are to outline three phenomena:

Flutter. One of the best known aeroelastic phenomena. Aeroelastic system offers dynamic properties under certain conditions lead to oscillations. It is a self-induced vibration that occurs when a bearing surface bends under downforce. Once the load is reduced, the deviation is also reduced, restoring the original form, this in turn restores the original charge and the cycle begins again.

At its most innocuous it may appear as a "buzz" in the structure of the plane, but in the more violent you can detonate at high speed uncontrollably and cause great damage or destruction of the aircraft. Perhaps the best example "sadly famous" l "flutter" is the Tacoma Narrows Bridge in Washington State (USA.), Which began to swing, self-excited, until completely destroyed.

dynamic response . Is the response of aircraft to gusts and other external atmospheric disturbances.

Batanea (Buffet). is a high frequency instability associated with a randomly forced vibration.

DNA / Aeroblog.

Source (s):

• PASSAGE TO SCIENCE