Support reaction type wind-tunnel balance shafting static calibration method

Abstract

The invention relates to a method for statically calibrating a body axial system of a bearing reaction wind tunnel balance, wherein a loading device is arranged on a connecting end of a supporting rod of the wind tunnel balance, and the displacement of the loading device of the wind tunnel balance is measured through a laser displacement sensor which is arranged on a rigid support; after the wind tunnel balance is loaded, the reading of the laser displacement sensor is acquired, and the displacement of the loading device of the wind tunnel balance and the displacement of various loading points are calculated; the load exerted is subjected to translation and synthesized on an origin of a coordinate system of a body axle, and the bearing reaction generated on the wind tunnel balance by a base on the origin of the coordinate system of the body axle is solved and taken as the load of the body axial system of the wind tunnel balance; and a static calibration formula of the wind tunnel balances is solved through the least square method and the Gaussian elimination method by combination of the increment of outputted voltage signals before and after loading of all the wind tunnel balances and the loads of body axial systems. The static calibration method can simplify a static calibration device of the wind tunnel balance, not only does not need to use a complex offset-type or single-vector motion mechanism but also does not need to be limited by the performance of a reference balance, and is simple to calculate due to fixed position of the body axial system of the wind tunnel balance compared with the displacement method of a measuring and loading device.

Description

technical field [0001] The invention relates to a method for static calibration of a wind tunnel balance shaft system, in particular to a method for static calibration of a support reaction force wind tunnel balance body shaft system, belonging to the field of wind tunnel balance calibration. Background technique [0002] The wind tunnel strain balance is a multi-component force sensor used in aircraft wind tunnel tests, which can measure the force and moment of the airflow acting on the aircraft model, and then combine the airflow parameters and wind tunnel model parameters to calculate the static and dynamic aerodynamic coefficients of the aircraft model. These wind tunnel test data are an important basis for aircraft design, so it is necessary to accurately calibrate the wind tunnel strain balance, and its uncertainty can only be used if it meets the requirements of the national military standard. [0003] The currently used wind tunnel balance calibration method after lo...

AI Technical Summary

Problems solved by technology

Among them, methods (1) and (2) require a mechanism that can perform multi-degree-of-freedom movements, and the machinery and control system are relatively complicated, the equipment cost is high, and maintenance is difficult; method (3) has high requirements for reference balances, and its development and calibration are difficult. It is quite technically difficult, and currently only two research institutions in Germany and Sweden have such equipment; the hardware system of method (4) is relatively simple, but it requires more complicated axis when calculating the axis position and gravity of the balance body, and the orientation of the loading cable. System conversion; method (5) is a unique technology of the Langley Center in the United States, which has extremely high requirements for the processing accuracy of the equipment and the accuracy of the testing system

Due to the difficulty of the above methods, many research institutions will ignore some secondary factors when developing the wind tunnel calm calibration equipment, and adopt a compromise plan, which increases the error of the system

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