Can I use predefined field to have a part increase in thickness both outwards and inwards?

[drennon236]

My assembly consists of inner steel part, outer steel part and concrete cylindrical part in the middle. I want to make contact between the different parts, so far I have assigned predefined field to make the inner steel part expand outwards, and outer steel part expand inwards (figure 3). I was wondering if it is possible to have the concrete cylindrical part expand both outwards and inwards as shown in figure 4, and have the steel parts remain unchanged. Is it possible to assign two predefined fields to the concrete part, or does it not make sense?

Assembly consists of three parts:

Predefined field for grout (concrete part):

Predefined field for two steel parts:

What I want grout to do so that it expands and makes contact with both steel parts. I want steel parts to remain unchanged.

 

[FEA way]

If you just want to establish contact then apply predefined temperature only to these two steel parts. Otherwise you would have to use some trick that may not work properly. For example partition the grout into two cylinders (one inside the other), somehow fix the nodes on the middle surface and apply predefined field to these two cells.

 

[drennon236]

Thank you. Could you help me explain to my manager why its a bad idea to only use predefined field on the grout? He seems adamant thats the way to go.

 

[FEA way]

Thermal expansion of the grout will bring its outer surface closer to the external tube but it will also move its inner surface away from the internal tube.

 

[drennon236]

Wait so thermal expansion moves the part as a whole closer to the outer steel part? I thought thermal expansion increases the thickness of the grout overall?

 

[drennon236]

Meaning grout will bring its outer surface closer to the external tube while not changing the inner surface.

 

[FEA way]

Thermal expansion of a cylinder increases both its external and internal diameter.

You can check this by performing analysis on a single heated cylinder.

 

[drennon236]

Of course, thank you