METHOD FOR EXPERIMENTAL DETERMINATION OF AERODYNAMIC CHARACTERISTICS OF A MODEL DURING QUASI-STATIC TESTS IN A WIND TUNNEL Russian patent published in 2019 - IPC G01M9/00 

FIELD: aviation.

SUBSTANCE: invention relates to experimental aerodynamics of aircraft during experimental research in a wind tunnel. Method consists in that the analyzed model is installed in the working part of the aerodynamic pipe on the supporting device. No flow is measured. After the pipe is set to the operating mode (preset flow rate is set) with the help of the drive, the model is moved along the angle of attack (sliding) from the initial to the specified final angle and back. Indications of aerodynamic scales, an angle of attack (slip) sensor and a pressure sensor with sampling frequency of not less than 1 kHz are recorded simultaneously with the beginning of movement and to its end. Further processing involves taking detrimental aerodynamic loads from measured readings, which are filtered with a Butterworth low-pass filter with cutoff frequency of 2–5 Hz. As a result, obtaining quasi-static aerodynamic dependencies, from which position of "catastrophic" transitions on angles of attack (slip), as well as angles of attack (slip) of the beginning of aerodynamic shaking and its development on angles of attack (slip) are determined.

EFFECT: location of features in the form of "catastrophic transitions" in aerodynamic characteristics, as well as in determination of angles of attack and sliding at which "pre-threshold" aerodynamic shaking and its development with increase of these angles begins to appear.

1 cl, 7 dwg