复合材料层合板分析课件.pptVIP

WS-* NAS121, Workshop , May 6, 2002 WS-* WORKSHOP Define a Composite Material NAS121, Workshop , May 6, 2002 Problem Description A 1 in. x 1 in. composite plate is loaded with 2000 #/in. in the Y direction on the top edge, 1000 #/in. in both the X direction and Y direction on the right hand side edge. The left side reacts the loads with X, Y, Z, and Ry constraints. Problem Description The layup is made of graphite/epoxy tape and is shown to the right. The angles shown are relative to the global axis shown. Thus, the 0 degree ply 1 has it’s fibers coming out of the page in the Y direction. Note that while the positive sense of the angles are right hand rule around the Z global axis in this layup definition, in the Nastran definition, it is around the Z element axis and thus dependent on the element GRID order. Problem Description (cont.) The composite plies are graphite/epoxy tape with a thickness of 0.0054 in. The elastic and strength properties are shown on the right. The failure theorem to be used is Hill. E11 20e6 E22 2e6 U12 .35 G12 1e6 G13 1e6 G23 1e6 Xt 120 ksi Xc 110 ksi Yt 13 ksi Yc 16 ksi S 14 ksi Sb 5 ksi Suggested Exercise Steps Create a geometry model. Use mesh seeds to define the mesh density. Create a finite element mesh. Apply boundary conditions to the model. Apply loads to the model. Define ply material properties. Check element normals Define composite material properties. Define a material coordinate system Apply the material coordinate system to the elements. Submit the model to MSC.Nastran for analysis. Attach xdb Results File Display ply stresses using MSC.Patran. View ply failure indices in MSC.Nastran Change layup to make failure indices below 1.0. Analyze the model with the new composite layup View the changed ply failure indices CREATE NEW DATABASE Create a new database called composite1.db: In File select New Enter composite1 as the file name Click OK Choose Default Tolerance Select MSC.Nastran as the Analysis Code Select Structura