Week 1 Spur Gear Challenge

STATIC STRUCTURAL ANALYSIS ON SPUR GEARS USNG DIFFERENT MATERIALS

Objective:-

1. Perform static structural analysis on spur gears and find out the Equivalent stress, Total deformation and stress intensity using-

i. Cast steel

ii. Cast bronze

iii. Cast iron

2. Which material will we choose for manufacturing of spur gears based on these results.

3. Find out the location for possible fracture.

Procedure:-

- Open the Ansys workbench and drag the static structural analysis system in the project schematic. Rename the project as ''spur gear analysis''.

- Double click on engineering data to add the material or we can click right mouse button and choose edit option from the drop down menu. Simply click in ''contents of engineering data'' to add matreial from the toolbox. Then, we have to manually feed the data of the properties.

Connections:-

- Go to connections>scope>contacts and select those 26 faces of left spur gear that will be in contact with right spur gear. Select the target faces of the right spur gear. Put contact type as frictonal, behaviour as symmetric.

- Formulation is used to define the behaviour of contacts that we specify. Augmented lagrange increases the stiffness and thus reduces the penetration and chattering of the model.

MESHING:-

we used element size as 1mm to get more accurate results. Use adaptive sizing as 'no', and smoothing as low. Smoothing helps to improve the element quality by moving the location of nodes with respect to the surrounding nodes. The low option controls the number of smoothing iterations.

ANALYSIS SETTING:-

- initial time step- 0.2

- minimum time step- 5E-2

- maximum time step- 0.5

- Enabling large deflection by ON will help the solver to consider the large strain happening, such as metal forming in a simulation and deflection.

JOINTS:-

- A Revolute jont between the ground to the left and right spur gears. Provide rotation to the right spur gear and moment to the left spur gear. We can feed the data for rotation in a tabular manner. Put the interval of 30 degrees for rotation.

- Insert the value for moment as -10000N-mm. The negative sign indicates the clockwise rotation of the gear.

SOLUTION:-

Equivalent (Von-mises) stress in spur gear for cast steel material:-

Total deformation in spur gear for cast steel material:-

Below table summarizes the values of equivalent stress, total deformation and stress intensity for the three cases:-

SR. MATERIAL EQUIVALENT TOTAL STRESS

NO. STRESS(MPa) DEFORMATION(MM) INTENSITY(MPa)

1 Cast steel 387.67 30 413.23

2 Cast bronze 361.4 30 387.86

3 Cast iron 381.4 30 404.95

CONCLUSION:-

- The above analysis suggests that the maximum stress will develope in cast steel(387.67), then in cast iron9381.4)and minimum in cast bronze(361.4).

- The total deformation remains same for all the three cases.

- Cast steel will also experiences high stress intensity then bronze and iron.

- Calculating the factor of safety for all the three materials we will get the highest FOS for cast iron . So, we will choose cast iron as manufacturing materials for the spur gear.