I PHONE BENDING SIMULATION

A) TITLE:- I phone bending simulation using ansys workbench 2019 V3.

B) OBJECTIVE :- To simulate the bending operation to study different parameters like equivalnet stress , equivalent plastic strain etc.

C) MODELING :- The model consisting of I phone with frame , display , inner body , the top eight top holding fingers and two bottom pushing fingers. the model is imported into the Ansys static structural geometry. the image-1 shows the bottom view of I phone with pushing fingers.

image-1

D) ANALYSIS :-

1) The dipslay is assigned with glass , the frame is assigned with aluminium alloy with non linear properties and the inner body is assigned with polyethylene properties. the eight top holding fingers are considered as rigid bodies.

2) The ansys generates the default contacts. Out of these contacts all contacts except the contact between frame and display are made frictionless. the frame and display contact is made as bonded as they will deform together.

3) All the holding fingers ( top eight) are assigned with fixed-ground joints (image-2) while the translational-ground joint has been assigned to bottom pushing fingers.(image-3)

image-2

image-3

3) The contact surfaces between pushing fingers and bottom face of I phone are assigned with 6 mm mesh size with low smoothing quality while the othere body is meshed with default setting.

4)The analysis is carried out into 8 steps with large defelction and stabilization on for 1st step.

5) The inner body side faces are made fixed while the frame is allowed to diaplace into Y direction only. The translational joints are assigned with max. 8 mm dispalcement in Y direction as shown in image-4.

Image-4

5) the simulation is then carried out and the results obtained are summarized below:-

E) RESULTS :-

1) total directional deformation

2) equivalnet stress in frame

3) equivalnet strain in frame

4) force reaction

5) FOS for the frame

• CASE -2

In this case the following changes are done -

1) the position of pushing fingers is changed as shown below. it has been shifted more close to the CG of the body.

2) the frame material is changed to aluminium alloy with the S-N curve values as follows.

RESULTS FOR CASE 2:-

1)Total directional deformation

2) equivalnet stress in frame

3) equivalnet strain in frame

4) force reation

5) FOS for the frame

6)Fatigue life for the frame

image-5

F) DISCUSSIONS:-

The results for case-1 and case-2 are tabulated below.

i) The directional deformation is more ( 8.33 mm) when the I phone is bent by pushing the fingers at sideways ( case-1). for both the cases it is maximum at the position where the pushing fingers are placed.

ii) The maximum equivalent stress in case-2 is 2977 MPa which is much more as compared to case-1 (408 MPa).

iii) The maximum equivalent strain values are almost same with very less variation.

iv) If we observed the force reaction values then it seems that when the I phone is tried to bent from the center ( nearer to CG) ( case-2) the force required to bend is much more ( 20 KN) than the case-1 ( 10 KN).

v) The maximum FOS for case -1 is 15 while for Case-2 it is 11.8.

vi) in case -2 , The fatigue life of frame is found out and the results can be oberved from image- 5.

note :- the simulation file is attached herewith.