Question regarding Springelements

Altair Forum User

Hi all,

 

I want to model a spring with constant force over its elongation. In PROP/TYPE4 I tried to set H₁=8, so I can insert a constant function in fctID₁₁(which defines Force vs spring length). When I tried to start my simulation an error occured 'Spring with null stiffness, K has to be bigger than 0'. From my understanding I wouldn't need to define a K-Factor as it's already defined in fctID₁₁..

 

Any ideas on how to model a spring with constant force? Is it possible to give a function for the K-Factor?

 

Regards

Kevin

Altair Forum User

Hi Kevin,

This approach seems fine.

I'll check for a simple test model and will share with you.

Altair Forum User

Hi George,

 

But if I enter a stiffness value, the Force will be calculated as F=K*x, in which the Force will not be constant as defined in fctID₁₁. In fact, there would be two diffrent Force values defined at each step if I understand correctly.

I'm looking forward to your test model.

 

Kevin

Altair Forum User

Hi Kevin,

You are right, from the function it will calculate.

II'm attaching a simple model with Type 4 spring. Works fine with H=0 and constant function, sample model is just 1 spring, imposed displacement extension and compression.

Force remains constant

Unable to find an attachment - read this blog

Altair Forum User

Alright! Thank you very much