Week 5 Bending of iPhone

OBJECTIVE :-

To carry out a static-structural analysis on an iPhone bending simulation to determine the capacity of the material used to make the frame of the iPhone (Aluminium Alloy NL). The analysis will involve two cases differentiated by the location of thumbs that will be the source of load on the iPhone. The following outputs are to be requested:

Directional deformation within the model
Safety Factor of Aluminium Alloy NL
Life of the Aluminium alloy for the case

CASE SETUP:-

• Select/create materials with required proprties from engineering data

Properties of Aluminum Alloy

Properties of Glass

Properties of Polyethylene

Properties of Structural Steel

• Importing the geometry in the space claim to check each part of the iPhone geometry and to check the surface damages for Case 1 and for Case 2 changing the position of the pushing fingers towards x = 22.5mm & z = 10mm.
• To improve simulation time and reduce the number of elements, we can merge certain faces on the fingers of the model using the merge faces tool in the repair tab.

Case 1

Case 2

• Rename each of the geometry as a frame, Display, Insides, Pushing fingers and other all top faces as fingers also assigning the materials to the frames as Aluminium alloy, Display as Glass, Insides as the Polyethelene, and the fingers as the structural steel.

• For the fingers and the pushing fingers, the stiffness behavior as Rigid.

Connections

Contacts

Two contacts between the fingers are unknown, so this connection is deleted and the other connection Rename based on the definition and the define the contacts for a display to frame as the type to be bonded and other all contacts to be frictionless.

Joints

The body to ground type fixed joint is given to the fingers and the translation joints given to the pushing fingers from the body to the ground.

Mesh

• Generated a defaut mesh for total body and refine the mesh at contact portion of pushing fingers and frame bottom surface using face sizing option.

Analysis settings

The 8 septs are given to the simulation of the iPhone bending, for the solver type as direct and the large deflection is ON, with the stabilization is constant and the energy dissipation as 0.1. All the output controls to be ON.

• Insert - fixed support. it is given to the Both sides of the internal component are selected as shown (after hiding the frame):
  
  

• We can then similarly add the displacement condition. For this, we shall be selecting 4 faces on either side of the frame. The X and Z components are constrained.

• Insert - Joint Load. This will be created for both the translational joints on the thumbs. The x displacement values are entered in the tabular column as shown:

RESULTS

Case 1:

Directional deformation for Phone Case

Equivalent stress for Phone Case

Safety Factor for Phone Case

Life for Phone Case

CASE 2

Directional deformation for Phone Case

Equivalent stress for Phone Case

Safety Factor for Phone Case

Life for Phone Case

Comparision

	Directional deformation	Equivalent stress	Safety Factor	Life
case-1	5.1746	549.81	0.4547	1e8
case-2	3.9952	365.76	0	1e8

Conclusion

Static-structural analysis was carried out on an iPhone case made of a Non-Linear Aluminium Alloy material undergoing bending. Two cases involving different load locations were simulated, analysed and compared. It was established that the case would fail in both instances from a safety point of view .case 2 exhibited better numbers in terms of stresses and deformation generated & Expected life is same for both cases.

Google drive link

https://drive.google.com/file/d/1yGZ13TQC9FmX_LkfLTyfjWr--1CxxfhP/view?usp=sharing