An Equivalent Modeling Method for U-Shape Clamp Connectors

The problems of prestressing and nonlinear contact in attitude and orbit control dynamic system affect the precision and efficiency of finite element modeling. In this paper, an equivalent modeling method is proposed to solve this problem. A simplified model is established by means of equivalent elastic modulus and adjusting binding region. Based on the connection structure of U-shape clamp, the connection relation of U-shape clamp is divided into two parts: clamp and constraint. Firstly, according to the torsional relationship between tightening torque and axial tension, the axial force on U-shape clamp was obtained. Based on Euler–Bernoulli beam theory, the relationship between the equivalent elastic modulus and axial force was derived, and the equivalent modeling method of U-shape clamp was formed. Secondly, the equivalent stress analysis method of the main contact parts was proposed for the constrained part. Based on the stress distribution results, the location and size of the binding region in the simplified model were determined. Finally, a high-precision simplified model of U-shape clamp connected valve structure is established. The relative error between the calculated results of the first three natural frequencies of the structure and the experimental results is less than 3%, which verifies the effectiveness of equivalent modeling of this kind of U-shape clamp connector.