ОГЛЯД ДОСЛІДЖЕНЬ ТА ОБҐРУНТУВАННЯ НОВИХ МАТЕМАТИЧНИХ МЕТОДІВ МОДЕЛЮВАННЯ АЕРОПРУЖНОСТІ КРИЛА З ЛЮФТОМ КЕРУЮЧИХ ПОВЕРХОНЬ

Abstract

The phenomenon of instability in flight due to the interaction of aerodynamic, elastic and inertial forces. could prove disastrous. Therefore, due importance is given to the aeroelastic analysis of the aircraft at the design stage. Free play, sometimes called play, occurs as a result of wear on parts such as lugs or moving mounts, often due to the aging of the aircraft. Excessive free play is detrimental to the flight safety of the aircraft. This can lead to catastrophic aeroelastic instabilities such as limit cycle oscillation (LCO), a phenomenon associated with sustained vibration of a fixed amplitude. LCO can accelerate the accumulation of structural fatigue damage and compromise controllability during flight. Aircraft control systems play a critical role in ensuring stability, maneuverability and flight safety. Over the past few decades, nonlinear aeroelasticity has received increasing attention. Advanced computational capabilities have stimulated renewed interest among researchers in re-examining the control surface free play problem with the goal of refining analytical models for greater accuracy. Both modern theoretical and experimental analyzes of free play have opened up new possibilities for the study of aeroelasticity. Despite the apparent understanding of the fundamental problem and the availability of numerous modeling approaches, freewheeling research continues to generate varied predictions regarding aeroelastic dynamic behavior and associated properties. Free play, defined as the sag or movement of mechanical connections between control inputs and aircraft control surfaces, is a ubiquitous aspect of control system design. While a little play may be tolerable, excessive play can lead to non-linearities and uncertainties, potentially compromising flight performance and safety. The aim of the article is to review existing methods of numerical research, analyze new mathematical methods for modeling aeroelastic vibrations and formulate the problem of developing safety criteria for transport category aircraft in terms of preventing elastic instability in the presence of free play in the control mechanism.