Condensation Modeling of Nonlinear Dynamics in Contact Region of Bolted Joint

In order to study the influence of nonlinear contact force, a new method for modeling the dynamic characteristics of the contact region of bolted joint is proposed. Based on hybrid coordinate modal reduction technique, the characteristic modes of the linear degree of freedom in the bolt connection model are truncated, and only the nonlinear dynamic characteristics of the contact region are retained. After introducing the contact coupling condensation point which can equivalently take the place of nonlinear characteristic, the nonlinear contact force of the contact area can be condensed to the point by using the coordinate transformation. The nonlinear force of the bolt contact area will be transformed into the nonlinear stiffness of the condensation point. Therefore, it can effectively reduce the number of degrees of the nonlinear coupling and the computing resources. Through theoretical calculation and experimental comparison, the effectiveness and feasibility of the proposed method is verified. This will la