Comprehensive test method for aircraft equivalent ground flutter

Abstract

In order to overcome the technical deficiencies that the prior art is short of a ground flutter test system method and evaluation indexes, the present invention provides an equivalent ground flutter comprehensive test method of an aircraft. The method can establish an aircraft elastic aerodynamic model described by a nonlinear partial differential equation by analyzing the influence of different temperatures, flight speeds, atmospheric densities, and airflow environments on elastic aerodynamic coupling of the aircraft; on the basis of the model, signal excitation / vibration pickup point layoutis optimized according to the existing test data analysis, the partial differential equation deconvolution method is used to acquire an aerodynamic input signal theoretical value, a multi-point distributed excitation force control method is used to effectively track the input signal theoretical value, accurately control the multi-point excitation force, and realize the effect that the multi-pointexcitation force simulates the aerodynamic force; an environment that a structural temperature test covers a wide range of temperatures is established, a special multi-point non-contact high-speed image and contact sensor integrated fusion detection method solves the problem that the contact sensor cannot accurately detect the structural vibration amplitude and frequency in ultra-low temperatureand high temperature conditions.

Description

technical field [0001] The invention relates to a ground comprehensive test method for flight safety of aircraft such as civil aircraft, fighter jets, and unmanned aerial vehicles, in particular to a comprehensive test method for equivalent ground flutter of aircraft, and belongs to the field of aerospace and information technology. Background technique [0002] Flutter is a large-amplitude vibration phenomenon that occurs when an elastic structure is coupled by aerodynamic, elastic, and inertial forces in a uniform airflow. For aircraft, vibration occurs after an uncertain disturbance in flight. At this time, due to the effect of the airflow, the elastic structure of the aircraft such as the wing, empennage or control surface will generate additional aerodynamic force; as an exciting force, the additional aerodynamic force will aggravate the vibration of the structure. At the same time, the damping force of the air on the aircraft structure tries to weaken the vibration; w...

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Problems solved by technology

[0006] In order to overcome the technical defect that prior art lacks ground flutter test system method and evaluation index, the invention provides aircraft equivalent ground flutter comprehensive test method, this method is by analyzing different temperature, flying speed, atmospheric density, airflow environment to aircraft Affected by the elastic-aerodynamic coupling, an elastic-aerodynamic model of the aircraft described by nonlinear partial differential equations was established; The convolution method is designed to obtain the theoretical value of the aerodynamic input signal, and the multi-point distributed excitation force control method is used to effectively track the theoretical value of the input signal, accurately control the multi-point excitation force, and realize the effect of multi-point excitation force simulating aerodynamic force; establish a structure The temperature test covers a wide range of temperature environments, using a dedicated multi-point non-contact high-speed image and contact sensor integrated fusion detection method, which solves the problem that the contact sensor cannot accurately detect the vibration amplitude and frequency of the structure under ultra-low temperature and high temperature conditions

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