Structural bending moment dynamic calibration method used in aeroelasticity wind tunnel test of elastic wing

Abstract

The invention discloses a structure bending moment dynamic calibration method used in an elastic wing aeroelasticity wind tunnel test. The method comprises the following steps: pasting a strain gauge on a to-be-measured load cross section of an elastic wing; the elastic wings are fixedly connected to the ground supporting mechanism; determining the frequency range and the amplitude of the exciting force during ground calibration, and setting the frequency change step length of the exciting force; obtaining a frequency response function of the strain value measured by the strain gauge under each frequency to the dynamic bending moment borne by the elastic wing; the elastic wing is fixedly connected to a wind tunnel supporting mechanism, a blowing test is carried out, the dependent variable of the section to be measured is measured through a strain gauge, and a time domain strain value measured by the strain gauge during the test is obtained; fourier transform is carried out on the measured time domain strain value to obtain frequency domain information, the frequency domain information is substituted into the frequency response function to obtain frequency domain information of the bending moment borne by the section in the test period, Fourier inverse transform is carried out on the frequency domain information of the bending moment, and time domain information of the bending moment borne by the section to be measured in the wind tunnel test is obtained.

Description

technical field [0001] The invention belongs to the technical field of aircraft detection, and in particular relates to a dynamic calibration method for structural bending moments in aeroelastic wind tunnel tests of elastic wings. Background technique [0002] Modern aircraft designs are increasingly demanding aeroelastic properties. The aeroelasticity test technology of the elastic model wind tunnel is an important means to measure the wing load under different flight speeds. With the development of domestic aircraft with large aspect ratio and long endurance, the stiffness of the wing is getting smaller and smaller, and the dynamic effect of the structural bending moment on the elastic wing under the action of aerodynamic force is becoming more and more obvious. In the project, strain gauges are mainly used to measure the section strain, and the measurement of the bending moment of the wing section in the wind tunnel test is realized by the method of ground calibration. ...

AI Technical Summary

Problems solved by technology

The traditional static calibration method ignores the influence of dynamic characteristics, and using the static calibration results to measure the dynamic bending moment of the elastic wing in the wind tunnel will inevitably produce large errors

Especially for modern aircraft with strict structural weight reduction requirements, the measurement error of the bending moment on the structure will inevitably lead to a decrease in the efficiency of structural design, which will adversely affect the performance and safety of the aircraft

[0004] Therefore, looking forward to a dynamic calibration method of structural bending moment in the aeroelastic wind tunnel test of elastic wing, which considers the dynamic characteristics of the wing's bending moment caused by structural elasticity, and reduces the impact caused by the traditional static calibration method ignoring the dynamic characteristics of structural bending moment. error

Images