Rigid Dynamic Analysis 허유정 - Egloos

1 New Features2/23/2007 2007 ANSYS, Inc. All rights New FeaturesANSYS, Inc. ProprietaryInventory #0023821-1 Rigid Dynamic Analysisin WorkbenchRigid Dynamic Analysisin Workbench2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Rigid Dynamic Analysis : Calculates Dynamic response of an assembly of Rigid bodies. Can be used to study the kinematics of an assembly. Bodies are linked via joints and 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS dynamics Inputs and outputs are forces, moments, displacements, velocities and accelerations. All parts are assumed Rigid (no stress/strain). Viscous damping is accounted for via spring 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc.

2 ProprietaryTraining ManualANSYS Dynamic Setup Solid geometry is used to define the model (no multibody parts). Parts are considered Rigid so density is the only required material property. To begin a Rigid Dynamic Analysis parts must have their stiffness behavior flagged as 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Joint Types There are 9 available joint types in Simulation: Fixed Joint Revolute Joint Cylindrical Joint Translational Joint Slot Joint Universal Joint Spherical Joint Planar Joint General Joint Remember, joint DOF are with respect to the joint s reference coordinate system. Examples follow .. 2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Joint TypesRevoluteCylindricalTranslationalSlo tSphericalPlanerUniversal2/23/2007 2007 ANSYS, Inc.

3 All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Types Revolute Joint: Constrained DOF: UX, UY, UX, ROTX, ROTYFreeFixed2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Types Cylindrical Joint: Constrained DOF: UX, UY, ROTX, ROTYF ixedFree2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Types Translational Joint: Constrained DOF: UX, UZ, ROTX, ROTY, ROTZF ixedFree2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Types Slot Joint: Constrained DOF: UY, UZFixedFree2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Types Universal Joint: Constrained DOF: UX, UY, UZ, ROTYF ixedFree2/23/2007 2007 ANSYS, Inc.

4 All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Types Spherical Joint: Constrained DOF: UX, UY, UZFixedFree2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Types Planar Joint: Constrained DOF: UZ, ROTX, ROTYF ixedFree2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Types Fixed Joint: Constrained DOF: All General Joint: Constrained DOF: Fixed All, Free X, Free Y, Free Z, Free All General joints allow configurations not covered by the basic joints shown on the previous pages. A free body must be linked to ground using a general BTG joint with Free All specified (recall that all bodies must be defined such that a path to ground exists via joints).

5 2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Springs can be added from the BTG or BTB menus. In BTG a reference CS is used to locate the ground 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Dynamic Solution Setup From the New Analysis menu choose Rigid Dynamic . The Analysis Setting branch contains the controls for setting up the Analysis : Number of steps Time step controls Output controls Solver tolerances Note, additional steps are generally used when loads are applied or removed or when load histories undergo abrupt 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Dynamic Solution Setup For Rigid Dynamic Analysis only inertial loads (acceleration and/or gravity) are used.

6 No loads or supports are used as in flexible body analyses. Joint conditions are used to apply all other loads as constants or time varying using tabular or functional definitions. Once inserted each joint in the model is available via the drop down list in the joint condition 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Conditions Joint conditions can be defined as constant, tabular or as a function. Tabular data can be input in the table in Simulation or in the Engineering Data application. Once entered in Simulation the data can be saved to the ED 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Conditions Functional joint conditions can be entered in the details or defined in the ED application.

7 From the EDA choose to Insert New Load History . Select the appropriate type and indicate the data is in the form of a 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Conditions Various mathematical functions and arithmetic operators can be used to construct functions using time as an independent variable. The function is displayed in function and graphical formats. Can type in functions or choose to insert 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Dynamic Postprocessing Results available from Rigid Dynamic analyses are deformations, velocities, accelerations and various probe results. As with other Analysis types results may be scoped to entire assemblies or to individual parts, surfaces, edges or 2007 ANSYS, Inc.

8 All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Dynamic Postprocessing Rigid Dynamic results are graphical, tabular or 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS Dynamic DemonstrationBody to Body RevoluteBody to Body RevoluteBody to Ground RevoluteBody to Body TranslationalBody to Ground Fixed2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS New Features2/23/2007 2007 ANSYS, Inc. All rights New FeaturesANSYS, Inc. ProprietaryInventory # New Features LectureWorkbench SimulationFlexible Dynamic New Features LectureWorkbench SimulationFlexible Dynamic Analysis2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc.

9 ProprietaryTraining ManualANSYS If inertial effects are significant, the use of static structural analyses is not sufficient in determining the Dynamic response of a system Flexible Dynamic analysisin Workbench Simulation provides users with the ability to determine the Dynamic response of the system under any type of time-varying loads. Unlike Rigid Dynamic analyses, bodies can be either Rigid or flexible. For flexible bodies, nonlinear materials can be included, and stresses and strains can be output. Flexible Dynamic Analysis is also known as time-history analysisor transient structural shown here is from an Autodesk Inventor sample model2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS From Rigid to FlexibleStep 1 - Add Flexible dynamics Analysis to solution leg of tree2/23/2007 2007 ANSYS, Inc.

10 All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS From Rigid to FlexibleStep 2 - Change part definition from Rigid to Flexible2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS From Rigid to FlexibleStep 3 - Preview Flexible Part Mesh 2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS From Rigid to FlexibleStep 4 - Set Analysis Options for time step etc. and solve2/23/2007 2007 ANSYS, Inc. All rights # New FeaturesANSYS, Inc. ProprietaryTraining ManualANSYS and Supports For flexible bodies, any type of load or support can be applied For Rigid bodies, acceleration load and joint conditions are available Multiple Steps are supported for load histories: Similar to the static case, user can easily define multiple steps As shown below, loads, supports, and joints may be deactivated or activated at any step simply by right-clicking on the Timeline.