How to simulate a support with different stiffness.
I have an electric motor and it shows various bearing vibrations on different foundations (in reality). The reason for such behaviour is the different stiffness of foundations. I want to figure out the stiffness values of these foundations by selecting different stiffness values in the mechanical.
I perform modal analysis and set the fixed support on the bottom of the motor. Then I get the natural frequencies of the motor on the max rigid foundation.
To simulate a not max rigid foundation I use a spring tool with a scope body to ground. First of all, I set a very high value of stiffness in order to check results with the fixed support tool I used before and to make sure that it has the same behaviour. I used the 1E+17 N/mm value of Longitudinal stiffness. But I have got the error below. It means that fixed support and spring tool with a huge value of stiffness behave differently.
So, I would like to ask you which tool should I use to set a different stiffness on foundations?