Dynamic load testing method for wind tunnel with large incidence angle and low frequency structure

Abstract

The invention discloses a large-angle-of-attack low-frequency structure wind tunnel dynamic load test method. The method comprises steps of a virtual model being constructed, the virtual model comprising a low-frequency structure and a thin-wall structure which are connected with each other, and the low-frequency structure being obtained according to a similar relational expression with a low-frequency structure of a real aircraft; simulating and calculating the stress change of the thin-wall structure when the low-frequency structure bears different loads, and marking the position where the strain of the thin-wall structure is greater than a set value; constructing a physical model according to the parameters of the virtual model; pasting a strain gauge at a mark position on the thin-wall structure of the physical model, carrying out ground loading on the physical model, and measuring and establishing a corresponding relation between ground data measured by the strain gauge and an applied load under different load conditions; performing a wind tunnel test on the physical model, measuring and recording wind tunnel data measured by the strain gauges under different flow field conditions, and obtaining a dynamic load borne by the physical model through a corresponding relation; and obtaining the dynamic load borne by the low-frequency structure of the real aircraft according to the similarity relational expression.

Description

technical field [0001] The invention belongs to the field of aerospace engineering, and in particular relates to a method for testing dynamic load in a wind tunnel of a low-frequency structure with a large angle of attack. Background technique [0002] When researching small-scale models with high angles of attack, it is often necessary to measure the dynamic loads on the structure under flow field conditions. The traditional load measurement method is carried out on the real aircraft, and the dynamic load conditions at different positions of the aircraft are directly measured by pasting strain gauges and other methods. [0003] The existing dynamic load measurement methods have the following problems: [0004] (1) The cost of measurement on a real aircraft is huge, and once an accident occurs, it will cause huge economic losses; [0005] (2) It is impossible to predict the load situation before the actual flight process. [0006] Therefore, it is expected that a new dyna...

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Problems solved by technology

[0004] (1) The cost of measurement on a real aircraft is huge, and once an accident occurs, it will cause huge economic losses;

[0005] (2) It is impossible to predict the load situation before the actual flight process

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