Week 2 Railwheel and Track

Objective:

Objective of the work is to simulate Static Structural analysis on Rail wheel and Track setup using Structural Steel as a material to find out Equivalent stress, Total deformation and Fatigue Life of the model. Apply load five times of the initial load and re simulate the analysis. After getting both the result need to analyse and compare the results of these two cases and conclude in each loading condition how the geometry changes it’s out put value.

Experimental Procedure:

To carry out Static structural analysis on Ansys workbench, several steps has been followed.

Case-1

1. Engineering Data: This is the first step, where we have to select the material on which the analysis would be carried out. Structural Steel has been chosen for base material of all three parts of the model.

1. Import Geometry: After assigning the base material of the geometry, the model has been imported in Ansys.
2. Model: This step is the major step of Analysis. After importing the model, need to click on “Edit” to open the “Model Window” where we can assign several constraint and Boundary condition.

Step-1(Geometry): Under geometry click on the imported model and assign the material individually.

Step-2 (Connections): First select the both contact and changed to base on Name selection and Flip the Contact, if it was not flipped. Under Connection have to insert “Contacts”, where have to assign “Frictional Contacts” for Wheel and Track and assign the Contact faces of the geometry and “Frictionless Contact” has been assigned to Wheel and Shaft.

Step-3 after Contacts has been given, need to assign “Joints. Track has been kept Grounded or fixed. “Translation joint” has been assigned to Wheel and Track. “Planar Joint” need to assign on the side face of the wheel, to maintain the perpendicularity in between wheel n track.

Mesh: Global Mesh setting size as 35 mm has been chosen and Smoothening has been kept Low for meshing the model. “Face sizing” has been applied on the contact surface of wheel and Track and Element size 20 mm has been kept.

Analysis Setting: There are several parameters have been modified for Solver for optimum error free result. Under “Step Control” No of step has been kept 5, “Auto time stepping” kept on, “Define by” Time and Initial, Minimum and Maximum time step have been modified. Kept all “OUTPUT Control” as on and under “Non-linear control” New ton Raphson method kept as “Unymmetric”.

Joint Load: In the first Case “Bearing Load” of 100000 N-mm has been inserted on the Inner surface area of Wheel at the Frictionless contact area.

Translation of wheel: Total 500 mm of translation of wheel on track, as 100 mm increment has been kept at Tabular format and translation should be on positive X direction, as the same direction of track.

4. Solution: To get the result as per the objective of the work have to insert Equivalent Stress, Total Deformation and Fatigue life. User Defined result has been introduced to check the deformation value for the cases.
5. Solve: To obtain the result click on Solve.

*** The same procedure has been followed up for the Case-2 (Only the Bearing load has been changed to 500000N-mm).

RESULT (CASE-1)

Equivalent Stress: The maximum stress is 221.77 Mpa and Minimum Stress is 6.1312e-12 Mpa

Total Deformation: Themaximum deformation is 999.36 mm and minimum deormation 2.8422e-14 mm

Fatigue Life: The maximum life is 1e6 and minimum is 17701

RESULT (CASE-2)

Equivalent Stress: The maximum stress is 896.16 Mpa and Minimum Stress is 2.5803e-10 Mpa

Total Deformation: Themaximum deformation is 999.78 mm and minimum deormation 2.8422e-14 mm

Fatigue Life: The maximum life is 1e6 and minimum is 316.38

Analysis on all two cases:

• The Maximum Equivalent stress has been found on Case 2 (896.16 Mpa) which is approximate four times the value of Case-1(221.77 Mpa). The stress value is below the UTS limit of the material, so both the design is safe, but for case-1 the stress value is very low.
• The Deformation value are almost the same in all two cases.
• Due to the undergo of higher loading condition in Case-2 (Min. life 17701), the minimum fatigue life has gone down drastically in comparson with Case-1 (Min. life 316). Though the maximum value are same in both cases but due to the mnimum life in case-2, there might chance of fatigue failure of the part.

User Defined Result:

The maximum deformation is 1.472e-16 mm

Conclusion:

It has been observed that after considered User defined result on Wheel for 100000N loading condition, result has very lower deformation value. The total deformation value considered the entire geometry to give the result. In case of uiser defined value, it only consider the seleted geometry and give the deformation result accordingly.