Learning Forum

[Daniel Sami HAMADE]

Hello,

I am trying to build an interference fit simulation between two steel cylinders in a 2D plane stress or plane strain model of a 30 degres pie slice. 

I tried to follow in details all the recommendations in the links below:
/forum/forums/topic/basic-interference-fit/
/forum/forums/topic/interference-fit-pressure/
https://youtu.be/5jH2Ox6-YkU

The problem is that I am getting a FEA contact pressure of 83 MPa, whereas the theoretical value is 75 MPa ! (same materials: E=200 000 MPa, vu=0.3, dimensions given in below Figure).

Could you help me solving this issue ? any recommendations ?

You can find below the links to the Ansys Archive .wbpz file 

--> Model1.wbpz

I also tried to build the same model in a 2D axisymetric view, but I also get 83 MPa and not 73 MPa 

--> Model2.wbpz

Thanks in advance,

Sami

[peteroznewman]

Hello Sami,

I looked at your model and found it is very well done. It has a good mesh and all the boundary conditions are correct.

I used an online calculator that uses Lame's equation to calculate the Interference pressure for the values in your model and it came up with 81.5 MPa which is close to the Ansys result of 83 MPa.

Regards,
Peter

[Daniel Sami HAMADE]

 

Hello Peter,

Thank you so much for solving my problem! ????

I had entered a wrong value for d0 in my calculations.

Just one last question concerning the values your entered in the online calculator.

If I use d=119.4 mm instead of d=120 mm –> I get a pressure of 82.3 MPa.

I consider that d is the nominal diameter of the interface (after press-fit), based on:

Norton Machine Design Integrated Approach – Norton

Shigleys Mechanical Engineering Eighth Edition Design – Budynas Nisbett

Regards,

Sami

 

[peteroznewman]

Hello Sami,

I did no testing of the online calculator and didn't lookup the equation in Shigley's, but it seems you have an Ansys model that agrees with Shigley which is encouraging.

Regards,
Peter