Method for changing the angular orientation of wind tunnel models in a wind tunnel experiment

Abstract

Method for changing the angular orientation of wind tunnel models in a wind tunnel experiment involves mounting the wind tunnel model on a flexible tape suspension of a 6-component balance, in both the horizontal and vertical planes during tests in the working section of the wind tunnel, which is equipped with a standard α-mechanism for adjusting the model’s angular position in the vertical plane. The wind tunnel model is mounted on the tape suspension of the balance using a support rod, which is designed with a rotating joint to position and secure the model at the desired angular orientation in the horizontal plane of the support rod. The support rod is mounted on the model’s standard suspension assemblies, where it rotates around the transverse axis of the balance together with the model via the standard α-mechanism. Blow-by tests are performed on the support rod itself without the model to determine and account for corrections to the model’s aerodynamic coefficients resulting from its influence. Additionally, the projections of the aerodynamic force and moment are sequentially transformed from the weight coordinate system to the desired one, taking into account changes in the actual values of the angles of attack and slip in accordance with the kinematic diagram of changes in the angular position of the wind tunnel model and the location of its conventional center of mass.