Knot making and buckling method for protection wire of low-speed wind tunnel flutter testing model

Abstract

The invention discloses a know making and buckling method for a protection wire of a low-speed wind tunnel flutter testing model. The method comprises: step one, a knotting position and a connecting point position of a protection wire are determined; step two, the protection wire is processed to form a first segment and a second segment; step three, the first segment and the second segment are overlapped and wound to enable the first segment and the second segment to form a knot in an overlapping and winding mode, wherein the know is located at the knotting position and has a circular ring and a watershed line overlapped on the circular ring, the circular ring is segmented into a first half ring and a second half ring by the projection of the watershed line on the circular ring, and the second segment passes through the first half ring, crosses over the watershed line and extends out of the second half ring. With the method, the knotting position of the knotted protection wire is prevented from shifting due to mutual pressing, buckling and friction of wire parts in the knot and the friction is increased when the wire is stretched tightly; and when the protection wire is loosened, the knot releasing becomes convenient. Therefore, the length of the protection wire can be adjusted easily to adapt to the change of the model balancing position.

Description

technical field [0001] The invention relates to the technical field of wind tunnel flutter tests, in particular to a low-speed wind tunnel flutter test model protection line knotting method, a low-speed wind tunnel flutter test model protection line and a wind tunnel flutter test system. Background technique [0002] During the low-speed wind tunnel flutter test, in order to avoid damage to the model and achieve the purpose of repeated use, protective wires are usually used to protect the model. During the blowing test, the protection line is in a loose state; when flutter occurs, the vibration amplitude of the model expands sharply, which may cause damage to the model. At this time, the protection line should be tightened quickly to protect the model. In order to achieve a good protective effect, the protective line is mostly made of thin steel wire rope. There are two commonly used fixing methods, one is to tie the end of the rope with a dead knot, and the other is to fol...

AI Technical Summary

Problems solved by technology

However, the method of tying the dead knot is extremely inconvenient in the process of adjusting the position of the knot, and the method of making the soft iron wire is less reliable, and the protective wire may move and fail.

Therefore, the effect of the existing commonly used fixing methods is not ideal, which brings great inconvenience to the test.

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