Boundary stiffness simulation system in full-dynamic vertical fin buffeting test for airplane strength test

Abstract

The invention provides a boundary stiffness simulation system in a full-motion vertical fin buffeting test of an airplane strength test, and belongs to the technical field of airplane testing. Comprising a mounting bottom plate connected with the ground through foundation bolts, a boundary dynamic stiffness simulation assembly arranged on the mounting bottom plate and a rotation dynamic stiffness simulation assembly arranged on the mounting bottom plate, and the boundary dynamic stiffness simulation assembly and the rotation dynamic stiffness simulation assembly are connected with an aircraft vertical fin; the bending support dynamic stiffness of the full-dynamic vertical fin structure in a real state is simulated through the boundary dynamic stiffness simulation assembly, and the corresponding box section thickness can be designed according to the modal frequencies of the first bend and the second bend of the vertical fin; the rotary supporting dynamic stiffness of the full-motion vertical fin is simulated through the rotary dynamic stiffness simulation assembly, and different elastic element thicknesses can be designed according to the first-torsion modal frequency and the second-torsion modal frequency of the full-motion vertical fin, so that it is effectively guaranteed that the main modal frequency of the vertical fin structure in the ground installation state is consistent with the main modal frequency of the vertical fin structure in the real flight state; and the accuracy of a full-motion vertical fin buffeting test result in an airplane strength test is improved.

Description

technical field [0001] The invention belongs to the technical field of aircraft testing, in particular to a boundary stiffness simulation system in a full-motion vertical tail buffeting test of aircraft strength testing. Background technique [0002] my country's advanced fighter jets have a fully-moving vertical tail design. During the flight of the aircraft, the vertical tail structure is not only subjected to conventional maneuvering loads, but also subjected to unsteady aerodynamic forces during flight at large angles of attack, covering the main modal frequencies of the vertical tail itself. Random vibration loads. [0003] In order to verify the reliability of the vertical tail structure under the superposition of such conventional maneuvering loads and buffeting random vibration loads, it is necessary to carry out the buffeting test of the vertical tail of the aircraft on the ground. An important key link in carrying out the ground test is to simulate the real install...

AI Technical Summary

Problems solved by technology

An important key link in carrying out the ground test is to simulate the real installation state and fix the vertical tail structure on the ground. In conventional static and fatigue tests, the ground fixing device only simulates the support mode of the real structure and ensures that the strength of the fixing device meets the loading requirements, and The simulation of the dynamic stiffness of the boundary is not considered, which will cause the main mode frequency of the vertical tail structure in the ground installation state to be inconsistent with the real flight state

In the vertical tail buffeting test, the inconsistency of the main modal frequencies of the vertical tail structure will cause the response of the vertical tail structure under buffeting random vibration loads to be inconsistent with the real state, thus affecting the validity of the results of the full-motion vertical tail buffeting test

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