Week 2 Railwheel and Track

REPORT :

AIM:

To perform static structural simulation on rail-wheel and steel track model with diffrent bearing loads, and compare Total deformation,Equivalent stress and life under the diffrent loads.

PROCEDURE :

1.Geometry :

• The model was loaded on space claim and material was selected as structural steel.
• Material properties:
  

2.Model Setup :

Connections & Joints:

• Frictional contact with coefficient of 0.3 was defined bewteen wheel and Rail track.
• Frictionless contact was defined between axle shaft and wheel.
• 'Translational' joint was deinfed for axle shaft.
• 'Fixed' joint was defined for rail track .
• 'Planar' joint was defined for rail wheel (so as the wheel stays on the same plane during motion)

Meshing :

• The default sizing was set as 50 mm .
• Face sizing of 35mm was defined between wheel rim and track ( as these part are in CONSTANT contact with each other).
• Mesh:
  
• No of elements : 6726
  No of Nodes     : 13304

Boundary Conditions :

• Bearing load of 100000 and 500000 N were applied saperately on rail wheel bearing in two diffrent models.
• Displacement of 500 mm was defined for axle shaft (in translational motion). 

RESULT :

Note:

Case 1 : model with bearing load 100000 N

Case 2 : model with bearing load 500000 N

1.Total deformation:

	Deformation (mm)
Case 1	1000.5
Case 2	1000.7

case 1:

case 2:

2.Equivalent stress :

Maximum stress (MPa)	whole setup	rail wheel	steel track
Case 1	85.42	85.42	72.148
Case 2	367.44	367.44	298.76

Case 1:

Case 2:

3.Fatigue Life:

Fatigue life (no of cycles)	Maximum	Minimum
Case 1	1000000	1000000
Case 2	1000000	3515.4

Case 1:

Case 2:

4.User defined result :

The maximum deformation in  user defined result generated in the case 1 is same as the solution generated by the ANSYS workbench, however the minimum deformation differs.

Expression used : sqrt(Ux^2 + Uy^2 + Uz^2)

ANYSYS generated total deformation:

User generated result:

5. Fcator of Safety :

• Case 1: 2.92
  Case 2: 0.68
• FOS for Case 2 is less than 1 , which exceeds the design parametre.
• Maximum stress permissible for this setup is <125 MPa.
• Bearing Load should not excede 100000 N so as for the longer life of the rail wheel and steel track.

CONCLUSION :

Since the applied bearing load in Case 2 is greater than Case 1, Case 2 depicts more amount of equivalent stress , strain and a shorter fatigue life, total deformation is same for both the cases. The bearing load on the Rail wheel should not excede 100000 N for better fatigue life of the Rail wheel and less wearing of steel track.