Spring 2007, MET 415 - FEA Applications I

Prof. Dave Johnson, dhj1@psu.edu, Penn State - Erie, The Behrend College

HW-4D:  3D Modeling

Concepts:

• 3D Modeling:  Shell -OR- Solid Elements ?
• Wall and Hole Constraints

  A corner bracket is made with 3 flat pieces of steel.  All three pieces are 1/8" thick and all meet at 90^o angles.

The bracket is mounted to a wall with two screws through the holes.

 The bracket has a load of 300 lbf distributed uniformly on the top surface, pushing down.

  Analyze this structure for a static loading using 3D solid elements and also with 3D shells.

With 3D shells - be sure your model is connected - not separate bodies.

1. A table comparing the results for the solid and shell elements trials (no. of nodes, no. of elements, solution time, max. deflection, maximum stress, also report the value and location of REAL max. stress, mesh error)

2. Plots showing each model's:

• element mesh

• constraints and loads

• total deformation

• vonMises stress  (if singularities exist - exclude their effect)

3. Hand Calculation

   • estimate max. deflection and stress and compare to the FEA results
     Include plot(s) to make proper comparison to the hand calc.