Adapting a contact-mechanics algorithm to predict damping in bolted joints using quasi-static modal analysis. (1st January 2021)

• Record Type: Journal Article
• Authors: Zare, Iman; Allen, Matthew S.
• Is Part Of: International journal of mechanical sciences. Volume 189(2021)
• Publication Date: 2021-01-01
• Subjects: Bolted joints -- Block Gauss Seidel -- Contact algorithm -- Quasi-static -- Nonlinear damping -- Coulomb friction; Mechanical engineering -- Periodicals; Génie mécanique -- Périodiques; Mechanical engineering; Maschinenbau; Mechanik; Zeitschrift; Periodicals; 621.05
• DOI: 10.1016/j.ijmecsci.2020.105982
• Languages: English
• ISSNs: 0020-7403

Abstract

Highlights: Static reduction used to accelerate contact analysis. Algorithm iterates on groups of nodes, improving efficiency for 3D problems Used to predict natural frequency and damping of modes of 2D and 3D FE models. The algorithm resulted in dramatic computational savings while providing good accuracy. Graphical abstract: Abstract: While a bolted joint can be modeled in commercial FE codes, even quasi-static analysis is extremely expensive due to the level of detail required to capture slip at the bolt interface. This is even worse for 3D cases where the solver must deal with the two-dimensional friction problem, making convergence more expensive. In order to address this issue, we present a quasi-static algorithm that greatly accelerates the analysis of 2D and 3D problems. This algorithm uses static reduction along with a new numerical method which is a hybrid between Block-Gauss-Seidel and Newton-Rhapson. A relaxed form of 2D frictional problem is presented in this algorithm which increases the efficiency of the method. In order to evaluate the performance of the algorithm, we apply the method to perform QSMA on 2D and 3D cases. QSMA uses a series of static loadings to predict the effective natural frequency and damping of each mode of a bolted structure as a function of vibration amplitude. In the cases studied here the algorithm resulted in dramatic computational savings while providing good accuracy as compared to simulations in commercial finite element software, both for the effective natural frequencies and damping and for the contact pressure distributions. To explore the robustness of the algorithm, the mesh density, preloads, and quasi-static force amplitudes are explored. The effect of the size of the reduced model on the accuracy of the result and the efficiency of the method is investigated in this paper.