Leaf Spring (Material, Contact, geometric nonlinearity)

Transcription

1 00 Summary Summary Nonlinear Static Analysis - Unit: N, mm - Geometric model: Leaf Spring.x_t Leaf Spring (Material, Contact, geometric nonlinearity) Nonlinear Material configuration - Stress - Strain Curve definition creation of Contact Condition - General Contact (Rubbing consideration) Boundary and Load conditions - Pinned, User defined - Translational Disp. Results verification - Total displacement - View of results in animation Leaf Spring

2 00 Analysis Summary Tutorial purpose Creation of nonlinear contact - Create nonlinear contact with manual contact function. - Define contact between surfaces which are not in contact at the initial stage of the analysis, but will enter in contact during the analysis - Make the model return to its initial position using Subcases Analysis Summary Target model Boundary Condition (Pinned, User defined) Load (Translational Disp.) Translational Disp. (After -ZAxis 8mm Translation, Return to its original position) Pinned User defined (X,YAxis Boundaries ) Leaf Spring

3 00 Analysis Summary Manual Contact Not in contact at the beginning of the Analysis. After a vertical displacement in the bottom direction, the contact will be established Contact establishment Contact establishment In this case, it is difficult to define automatically the contact when the spring isn t in contact with the plate. The user has to define manually the surfaces where the contact will be established. Let s see how a manual contact can be assigned in the Step 07 of this tutorial. Leaf Spring

4 0 Model > Geometry> Import Click on [ ] (New) Icon. Click on [Geometry] - [Import]. Model: Select Leaf Spring.x_t. Uncheck [Search Contact Faces]. Click on [Open]. Tutorial Models are at the same location than midas NFX in the folder Manuals / Tutorials /Files If the option [Search Contact Faces] is checked, contacts will be automatically defined to the faces in contact. The purpose of this tutorial is to learn how to apply the contacts, so we will uncheck this option. Please verify the length unit of the model! Leaf Spring

5 0 Model > Geometry> Material Click on [Geometry] - [Material]. ID:, Name: Enter Spring. Select [Nonlinear] Tab. Type of Material nonlinearity: Select "Elasto Plastic". Elastic Modulus: Enter 69.. Poisson's ratio: Enter Check "Stress strain Data". 7 Click on the icon "Data Creation". 6 7 By clicking on this Tab, a nonlinear material is automatically defined. Explanation continues On the next page Enter the Stress - Strain Curve. Leaf Spring

6 0 Model > Geometry> Material Name: Enter Nonlinear Material. Strain: (0), Stress: (0) Strain: (0.00), Stress: (6.70) Strain: (0.0000), Stress: (6.70) Strain: (0.0087), Stress: (76.) Strain: (0.08), Stress: (.96) Strain: (0.070), Stress: (8.6) Strain: (0.07), Stress: (.) Strain: (0.060), Stress: (9.) Strain: (0.087), Stress: (.7) Strain: (0.07), Stress: (8.) Strain: (0.), Stress: (60.0) Click on [OK]. Stress - Strain Data: Select Nonlinear material. Click on [OK]. For this tutorial, a plastic type stressstrain curve is used. The second point 0.00 is the last point of the elastic section for this material and then it will be defined as the yield stress. Leaf Spring 6

7 0 Model > Geometry> Material Click on [Geometry] - [Material]. ID:, Name: Enter Rigid. Elastic Modulus: Enter.e. Poisson's ratio: Enter Click on [OK]. Leaf Spring 7

8 0 Model > Geometry> Material (Material Assignment) After selection of the model in the working window, Right-click with the mouse. Select [Material] >[Spring]. Leaf Spring 8

9 06 Model > Geometry> Material (Material Assignment) After selection of the model in the working window, Right-click with the mouse Select [Material] > [Rigid]. Leaf Spring 9

10 07 Model > Geometry> Contact Click on [Geometry] - [Contact]. Select [Manual Contact] Tab. Select "Surface to Surface Contact". Contact Type: Select "General contact". Master Faces: Select Surface. (Select the upper face of the plate.) Slave Faces: Select Surfaces. (Select the both side surfaces below the spring model.) Click on the icon [ ] at the right of the contact parameters. ID:, Name: Enter Friction. Coefficient of Static Friction : Select 0.. Click on [OK]. Contact Parameters: Select Friction. Click on [OK]. 8 General Contact: if general contact is used between two surfaces, when these two surfaces are in contact or not, the analysis is always possible, Master plane is displayed in red, whereas slave plane is displayed in blue Leaf Spring 0

11 08 Model > Boundary > Support Click on [Boundary] - [Support]. Click on [ ] (Top) Icon. Name: Enter Support. Target: Select Surfaces (Reference 6 Picture) Condition: Select [Pinned]. Click on [Apply]. 6 Leaf Spring

12 09 Model > Boundary > Support Name: Enter X,Y Fix. Method: Select [User defined]. Target: Select Plane. (Reference picture) DOF: Select [Tx], [Ty]. Click on [OK]. In order to restraint the movement of the spring in Z direction only, we have to fix its translation in X and Y directions. Leaf Spring

13 0 Model > Static load >Translational Disp. Click on [Static Load] - [Translational Disp.]. Click on [ ] (Isometric). Name: Enter 8mm Translation. Target: Select Plane. (Reference picture) Components: Check [ZAxis], 6 Enter -8. Click on [Apply]. The spring model will be moving of 8mm in the Z direction After the movement down of the spring, the spring will return to its initial position (next page) 6 Leaf Spring

14 Model > Static load >Translational Disp. Name: Initial position 입력. Target: Select Plane. (Reference picture) Components: Check [ZAxis], Enter 0. Click on [OK]. The spring returns to its initial position. In analysis case, a subcase will be created and Initial position will be associated to it. Leaf Spring

15 Model > Mesh > Auto Mesh Click on [Mesh] - [Auto Mesh]. Target: Select All the Models ( Models). Select High Speed Tetra Mesher Click on [OK]. Leaf Spring

16 Analysis and Results > Analysis Case > Creation (Subcase Setting) Click on [Analysis case] - [Create]. Name: Enter Leaf Spring. Analysis Type: Select [Nonlinear static]. In the bottom corner of the window [Subcase Setting], click on [Create] and choose [Nonlinear Static Analysis] to create a new Subcase. Subcase creation Leaf Spring 6

17 Analysis and Results > Analysis Case > Creation (Subcase Setting) <Change Subcase name> Select Nonlinear Static Analysis (Required), press the button F of the keyboard and enter 8mm Translation Select Subcase#, press the button F of the keyboard and enter Original position. <Analysis Condition Activation> By clicking on the Icon [ ] at the left of the Active part Sets, you can move the Analysis conditions to the newly created Subcase. Leaf Spring 7

18 Analysis and Results > Analysis Case > Creation (Subcase Setting) In the Subcase 8mm Translation, Select the Load Original position and Do a Drag-and-drop with the mouse to drop it in the window All Sets. In the Subcase Original position, Select the Load 8mm Translation and Do a Drag-and-drop with the mouse to drop it in the window All Sets. In the first Subcase, the spring is moving down of 8mm. In the second Subcase, the spring returns to its initial position. Leaf Spring 8

19 6 Analysis and Results > Analysis Case > Creation (Analysis Control) Click on [ ] (Analysis Control) Icon. Select [Nonlinear] Tab. Number of increments: Enter 0. Check [Displacement], Uncheck [Load], 6 Check [Work]. Check [Geometry Nonlinear]. Click on [OK]. 7 Click on [OK]. 7 Total displacement (8mm) will be calculated in 0 time steps. To allow large deformations, Geometry nonlinear option should be checked. 6 Leaf Spring 9

20 7 Analysis and results > Analysis > Perform Click on [Analysis] - [Perform]. Click on [OK]. Save with another Name: Enter Leaf Spring. Click on [Save(S)]. When the analysis perform is launched, Midas NFX Solver will automatically begin to work. You can stop the analysis by pressing the button Stop Execution! Leaf Spring 0

21 8 Analysis and Results working Tree> Leaf Spring > Nonlinear Static Analysis > Total displacement (8mm Translation) Select Real Scale. In the Analysis and results working Tree, double-click on 8mm Translation INCR=, Total displacement Click on [ ] (Multi - Step animation Recording). Click on [ ] (Play) Icon This is the analysis result of the 8mm down translation. the animation can be displayed from step to. Leaf Spring

22 9 Analysis and Results working Tree> Leaf Spring > Nonlinear Static Analysis > Total displacement (Original displacement) Select Real Scale. In the Analysis and results working Tree, double-click on Original position INCR=0, Total displacement Click on [ ] (Multi - Step animation Recording). Click on [ ] (Play) Icon As the model is subject to large deformations, the material is in plastic deformation state and can t return to its original state After the 8mm down translation, the spring returns to its original position. the animation can be displayed from step to 0. Leaf Spring