Hertz Contact MSC Marc 2005 r 2 MSC

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Hertz Contact MSC. Marc 2005 r 2 MSC. Patran 2005 r 2 Estimated Time

Hertz Contact MSC. Marc 2005 r 2 MSC. Patran 2005 r 2 Estimated Time for Completion: 30 minutes Experience Level: Lower

Topics Covered • Creating deformable contact boundary conditions of two bodies • Controlling solutions

Topics Covered • Creating deformable contact boundary conditions of two bodies • Controlling solutions for nonlinear geometric effects • Reviewing the results and comparing to a theoretical value • Using local adaptive meshing 2

Problem Description • In this example problem, a steel cylinder with a radius of

Problem Description • In this example problem, a steel cylinder with a radius of 5” is pressed against a 2” deep aluminum base. The problem is linear except the contact condition at the base which is modeled using the contact pair approach. • We will use Patran to complete the problem description from a given 2 D meshed model and analyze it by using Marc. 3

Summary of Model 10, 000 psi pressure Steel E = 30 E 6 v

Summary of Model 10, 000 psi pressure Steel E = 30 E 6 v = 0. 30 Constrain 2 nodes along the vertical center line <0, , > Aluminum E = 10 E 6 v = 0. 33 Constrain any node along the vertical center line <0, , > 5” radius 2” 16” Constrain all bottom nodes <, 0, > 4

Goal • In this example, we will determine the maximum compressive stresses in a

Goal • In this example, we will determine the maximum compressive stresses in a cylinder and a flat plate being compressed against each other. • The results from Marc will be compared to a theoretical value. • We will also demonstrate how the results can be improved through the use of adaptive meshing. 5

Expected Results Maximum compressive stress is 2. 12 E 5 psi. Y-Component stresses Results

Expected Results Maximum compressive stress is 2. 12 E 5 psi. Y-Component stresses Results WITHOUT the use of adaptive meshing 6

Expected Results Maximum compressive stress is 2. 38 E 5 psi. Y-Component stresses Results

Expected Results Maximum compressive stress is 2. 38 E 5 psi. Y-Component stresses Results WITH the use of adaptive meshing 7

Create Database a a. b. c. d. e. Click File menu / Select New

Create Database a a. b. c. d. e. Click File menu / Select New In File Name, enter hertz. db Click OK Select Analysis Code to be MSC. Marc Click OK b d c e 8

Import Model a b c d a. b. c. d. Click File menu /

Import Model a b c d a. b. c. d. Click File menu / Select Import Select Source to be MSC. Patran DB Locate and select file hertz_model. db Click Apply 9

Create Fixed Displacements b c a a. b. c. d. e. f. g. h.

Create Fixed Displacements b c a a. b. c. d. e. f. g. h. i. j. k. l. m. n. Click Loads/BCs icon Select Action to be Create Select Object to be Displacement Select Type to be Nodal In New Set Name, enter fixed_base_x Click Input Data In Translations, enter <0, , > Click OK Click Select Application Region Select Geometry Filter to be FEM In Select Nodes, select any node along vertical line of the base from screen or enter Node 1167 Click Add Click OK Click Apply d g h e f j i n k l Repeat (e) – (m) for the following new sets of BCs New Set Name Translations Application Region fixed_base_y < , 0, > All nodes at bottom of base (Node 1145: 1189) fixed_cylinder_x <0, , > Any two nodes along vertical center line of cylinder (Node 326 327) m 10

Create Deformable Contacts e a f a. b. c. d. e. f. g. h.

Create Deformable Contacts e a f a. b. c. d. e. f. g. h. i. g Select Object to be Contact In New Set Name, enter base_contact Select Target Element Type to be 2 D Click Select Application Region Select Geometry Filter to be Geometry In Select Surfaces, select base on screen or enter Surface 3 Click Add Click OK Click Apply h Repeat (b) – (i) for the following new set of BCs New Set Name cylinder_contact Application Region Two surfaces on cylinder (Surface 1 2) b c d i 11

Create Pressure a a. b. c. d. e. f. g. h. i. j. e

Create Pressure a a. b. c. d. e. f. g. h. i. j. e Select Object to be Pressure In New Set Name, enter pressure Select Target Element Type to be 2 D Click Input Data In Edge Pressure, enter 10000 Click OK Click Select Application Region In Select Surfaces or Edges, select edges on top of cylinder and click Add to add the selected edge to Application Region one by one or enter Surface 1. 4 2. 2 Click OK Click Apply f b c d h g j i 12

Define Material a a. b. c. d. e. f. g. Click Materials icon In

Define Material a a. b. c. d. e. f. g. Click Materials icon In Material Name, enter steel Click Input Properties In Elastic Modulus, enter 30 e 6 In Poisson Ratio, enter 0. 3 Click OK Click Apply d e Repeat (b) – (g) for the following new material Material Name aluminum Elastic Modulus Poisson Ratio 10 e 6 0. 33 b c f g 13

Define Element Properties b a a. b. c. d. e. f. g. h. i.

Define Element Properties b a a. b. c. d. e. f. g. h. i. j. Click Properties icon Select Type to be 2 D Solid In Property Set Name, enter cylinder_prop Click Input Properties Click Mat Prop Name icon and select steel In Thickness, enter 1 Click OK In Select Members, select surfaces of cylinder on screen or enter Surface 1 2 Click Add Click Apply c e f d h Repeat (c) – (j) for the following new property i Property Material Thickness Members Set Name base_prop aluminum 1 Surface of base (Surface 3) j g 14

Modify Solution Control and Run Analysis a a. b. c. d. e. f. g.

Modify Solution Control and Run Analysis a a. b. c. d. e. f. g. Click Analysis icon Click Load Step Creation Click Solution Parameters Select Nonlinear Geometric Effects to be None Click OK Click Apply (answer Yes to modify the Default Static Step) Click Apply ** Wait until analysis is completed ** d c b g e f 15

Read Results File a a. b. c. d. e. Select Action to be Read

Read Results File a a. b. c. d. e. Select Action to be Read Results Click Select Results File Locate file hertz. t 16 Click OK Click Apply c b d e 16

Plot Results a a. b. c. d. e. f. Click Results icon In Select

Plot Results a a. b. c. d. e. f. Click Results icon In Select Result Cases, select the last increment In Select Fringe Result, select Stress, Global System Select Quantity to be Y Component In Select Deformation Result, select Displacement, Translation Click Apply b c d e Maximum compressive stress is 2. 12 E 5 f 17

Theoretical Comparison 18

Theoretical Comparison 18

Theoretical Comparison Maximum compressive stress Max c Theoretical Marc % Difference FEA 2. 309

Theoretical Comparison Maximum compressive stress Max c Theoretical Marc % Difference FEA 2. 309 E 5 19

Turn On Adaptive Meshing and Run Analysis a a. b. c. d. e. f.

Turn On Adaptive Meshing and Run Analysis a a. b. c. d. e. f. g. h. i. j. k. Click Analysis icon In Job Name, enter hertz_amesh Click Job Parameters Click Adaptive Meshing Select Adaptivity Type to be Local In Zone Name, enter contact_zone In Select a Group, select all Click Apply Click OK Click Apply e d f ** Wait until analysis is completed ** g b c h k i j 20

Read Results File a a. b. c. d. e. Select Action to be Read

Read Results File a a. b. c. d. e. Select Action to be Read Results Click Select Results File Locate file hertz_amesh. t 16 Click OK Click Apply c b d e 21

Plot Results a a. b. c. d. e. f. Click Results icon In Select

Plot Results a a. b. c. d. e. f. Click Results icon In Select Result Cases, select the last increment In Select Fringe Result, select Stress, Global System Select Quantity to be Y Component In Select Deformation Result, select Displacement, Translation Click Apply b c d e Maximum compressive stress is 2. 38 E 5 f 22

Investigate Modified Meshes have been refined automatically where the contact occurred, giving more accurate

Investigate Modified Meshes have been refined automatically where the contact occurred, giving more accurate results. 23

Theoretical Comparison • Investigate the improvement in the results when using adaptive meshing Maximum

Theoretical Comparison • Investigate the improvement in the results when using adaptive meshing Maximum compressive stress Max c Theoretical Marc 2. 309 E 5 Marc with adaptive mesh 2. 309 E 5 % Difference FEA Use of adaptive meshing, which refines meshes in the contact zone, can improve the accuracy of the results without having to refine meshes of the entire model. 24