S7-1 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation SECTION 7 MAKING LAYUPS WITH MSC.LAMINATE MODELER

S7-2 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation

S7-3 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation BASICS FOR LAYUPS n A layup is composed of a stack of plies n A layup is created, in MSC.Laminate Modeler, from a list of plies. The plies in the list are to be in the order they are to be applied to the model. n Plies are applied from the direction used to create them. The direction of application can easily be changed. n Plies may be used repeatedly in a layup. Make sure to specify the application direction(top or bottom) as needed.

S7-4 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation CREATING LAYUPS n MSC.Laminate Modeler layup menu u Step 1: build a layup out of an existing set of plies u Step 2: define offset relative to the application region u Step 3: select element type u Step 4: specify tolerance for properties translation n The four submenus are shown below Step 1 Step 2 Step 3 Step 4

S7-5 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation STEP 1: LAYUP FROM PLIES n This menu is used to specify u Plies to be used for layup u Order of plies l In this example Ply_1 is to be applied to the model first and third, and Ply_2 is to be applied second and fourth. u Any symmetry of plies n Tools are available for replicating and editing list of plies

S7-6 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation n Copy ply selections(LM_Layup definition) symmetrically about below the bottom ply(LM_Ply) n Copy ply selections symmetrically about bottom ply n Copy ply selections, keeping the same order, to below the bottom ply n Copy ply selections that are above the bottom ply, keeping the same order, to below the bottom ply n Remove selected cells n Copy selected cells n Paste cells into selected location n Paste cells using mirroring n Undo last action in LM STEP 1: LAYUP FROM PLIES (Cont.)

S7-7 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation STEP 2: SPECIFY ELEMENT OFFSET MIDDLE BOTTOM TOP (Shell element) surface, Select Area Offset Value (Shell element) surface Offset Value View Direction Default is Middle (no offset) Reference plane (Shell element) surface, Select Area Definition point

S7-8 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation n Offsets when used correctly can improve the accuracy of your analysis n When incorrectly used an offset can cause large reductions in stiffness. u Understand the load paths l How are the bending moments from the offset reacted? l Do not fix offset elements in translation only n Do not use offsets when performing buckling analysis. u The differential stiffness calculations do not consider offsets u Run analysis as non-linear ? l The same differential stiffness limitation exists STEP 2: SPECIFY ELEMENT OFFSET (Cont.)

S7-9 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation STEP 3: SPECIFY ELEMENT TYPE n Select either standard or revised shell element type. n It is recommended to use the standard element type; this is the default.

S7-10 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation n MSC.Laminate Modeler has a default global tolerance that is used by the program to calculate how many material property sets need to be created in MSC.Patran. n Can change this tolerance, or create a local tolerance to match requirements. STEP 4: GLOBAL OR LOCAL TOLERANCE Local region Global region

S7-11 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation VERIFYING A LAYUP n The created layup can (and should) be verified visually to see that it is what is desired

S7-12 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation SHOW LAYUP CROSS-SECTION n The cross-section of a layup, showing its thickness and offset, can be displayed drawn on a plane n Show/LM_Layup/Element does the same thing, but for a set of elements

S7-13 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation TRANSLATING FROM PLY LAYUP TO LAMINATE MATERIALS n When Apply is clicked in the LM_Layup menu, the plies(LM_Ply) are used to create laminate material in the traditional sense n This is done automatically by MSC.Laminate Modeler when executing an analysis n This is an internal program function, and really is what is desired to avoid doing manually Laminate material description LM_Ply ply description

S7-14 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation n A minimum set of laminate materials is created to model the fibre angles within the user-defined tolerances n If the tolerance is zero, there will be one laminate material per element n A property set is made for every laminate material generated n A group is made for each ply(its application region), for reference purposes n The user is informed about the number of materials and property sets that are defined TRANSLATING FROM PLY LAYUP TO LAMINATE MATERIALS (Cont.)

S7-15 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation RELATIONSHIP OF PLIES TO LAMINATES n Plies in a layup u A ply may change level/depth, but will always be continuous n Layers in laminate u A layer has constant level/depth, but may have several plies Element Grid Ply A Ply B Ply C Ply D Ply E Layer 1 Layer 2 Layer 3 Layer 4 Layer 5

S7-16 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation CUSTOM LAYUP DEFINITION n Ply angles in MSC.Laminate Modeler layups are calculated from the edge of the elements first two nodes. This is only one of the methods for defining ply angles in MSC.Nastran. n To specify alternative definitions in MSC.Laminate Modeler the Create/Laminate menu can be used. This menu allows ply angles to be defined relative to a vector or a coordinate system projected onto the element. Secondary vectors or coordinates are used for the elements which are nearly normal to the vector being used.

S7-17 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation CREATE/LAMINATE FORM n Select the method for defining the zero degree direction

S7-18 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation LAMINATE OPTIONS… n Shear Correction allows material properties to be modified for large draping shears n Ignore Thickening keeps plies at their unsheared thickness n Equally Spaced Variables makes draped angles equally spaced (i.e. 5,10,15 degrees)

S7-19 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation VERIFYING LAMINATE MATERIAL n It is possible to investigate the laminate created in the layup process. n Different options under Display Method will give different types of plots.

S7-20 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation n Display Method XY Plot graphically shows either thickness or orientation of the plies. VERIFYING LAMINATE MATERIAL (Cont.)

S7-21 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation TRANSFORMING A LAYUP BY MIRROR n Allows a ½ model to be mirrored and the plies to be mirrored at the same time. n Adds the new elements to the layup file and extends the plies n Plies crossing the mirror plane at an angle are not correctly draped so this is an approximate modeling method.

S7-22 PAT325, Section 7, February 2004 Copyright 2004 MSC.Software Corporation