Week 1 Spur Gear Challenge

OBJECTIVE

Static Structural analysis of spur gear to find out the equivalent stress , total deformation and Stress intensity by using below listed materials.

• Cast iron 
• Cast steel
• Cast Bronze

Compare the results obtained by using 3 different materials for gears and find location for possible fracture.

PRODECURE

Static structural analysis is carried out on spur gear by using ansys workbench.

• Create static structural analysis and in engineering data select the material castiron , cast Steel and Cast Bronze.
• Import the geometry and check in SpaceClaim for any irregularties.

                                                 

• Then open Ansys mechanical and rename the geras and assign the material according to the cases.

                                           

• Contacts     Contact created between the both spur gear .The contact type is frictional with the mating surface of gears selected as Contact and target .The behaviour is changed to Symetric and the formulation type used in Augmented lagrange .The interface treatment is set to adjust to touch.

                    

• Joints    Joint set for both the gears as the revolute and body  ground.

                    

                                                                      

• Mesh        The gear is meshed with the size of 0.5mm .A mesh metric that identifies the element according to thier quality.

                                                  

• Analysis Setting The simulation runs for 6Steps So that the number of steps is set as 6 Define by time and large deflection is set to on.

                                                                                 

• JointLoad   One of the gears is given rotation for six time steps and the other is given a constant moment.

                                         

                                           

                                          

Now for different materials mentioned below the is selected one by one run the simulation to find out the equivalent stress Total deformation and stress intensity.

• Case 1 Cast iron
• Case 2 Cast Steel
• Case 3 Cast Bronze

Case 1 Cast Iron

                                                             

Equivalent Stress Max   466.09 Mpa

                   

                             

Total Deformation 30mm

                          

                                

Stress Intensity 525.12 Mpa 

                                    

                                 

                                             

Equivalent Stress

Case 2 Cast Steel

Material Data

                                                                  

Equivalent Stress Max 460.21Mpa

                                   

                          

Total Deformation Max 30mm

                            

                             

Stress Intensity Max 516.79 Mpa

                             

                                      

                                        

Equivalent Stress 

                       

Case 3 Cast Bronze

Material Data

                                              

Equivalent Stress Max  422.83 Mpa

                                       

                                    

Total Deformation Max 30mm

                                       

                                 

Stress Intensity Max 493.73 Mpa

                                  

                                    

                                   

Equivalent Stress

Result and Conclusion

The analysis runs successfully and results are obtained for all the cases.

                                       Equivalent Stress Max Mpa          Total Deformation Max mm         Stress Intensity Max Mpa

Cast Iron                                 466.09                                           30                                              525.12

Cast Steel                               460.21                                            30                                              516.79

Cast Bronze                             442.83                                           30                                              493.73

• From the above comparsion cast bronze shows less impact compared to the others
• Equivalent stress and stress Intensity of cast steel is slightly below as compared to cast iron  the ltimate strength of cast iron is higher than cast steel and hence will run for a few more cycle .So that life will be good and also the cost of the material is less compared to remaining and every material having thier own advantages so based on customer requirement depending on 
• Crack is most likely to occur near at the root of the tooth.
• Deformation for all three materials is the same.

LINK : https://drive.google.com/file/d/1-Aiv-uxW-C_3wlzd6RldtFLnfkauxth6/view?usp=sharing