Analysis of the Influence of Temperature Gradient on the Measurement Accuracy of Axial Force in Balance

Abstract

As a measuring element in wind tunnel test, it is important to ensure the measurement accuracy of strain balance.However, in the continuous wind tunnel, due to the long running time of the wind tunnel and the continuous transformation of Mach number, the temperature distribution of the balance body will be uneven, resulting in temperature gradient.This temperature gradient has an obvious influence on the measurement accuracy of the axial force of the balance.In order to explore the influence of temperature gradient on the axial force and strain output of the balance in the continuous wind tunnel, three temperature loading conditions were summarized according to the actual working conditions, and the thermal-solid coupling analysis of the 80A balance was carried out by ANSYS Workbench.The results show that the higher the temperature of the base point of the temperature gradient is, the faster the temperature input is, the more uneven the temperature distribution of the balance is, and the larger the temperature gradient is, the larger the axial force and strain output is. Considering the heat conduction of the back support rod, the temperature distribution of the balance body is relatively uniform, the temperature gradient is small, and the output of axial force and strain is small.