Split volume in either SOLIDWORKS
 

Dear all,
I want to simulate a heat exchanger which consists of a helix pipe with hot fluid flowing through it and an outer pipe which is full of cold fluid. I draw the geometry in Solidworks. Pleae take a loot at the two pictures at the attachments.

Picture 1. This is the helix pipe without the outer pipe extruded-though you can see the sketch of the outer pipe.
Picture 2. This is the final shape after I extruded the outer pipe.

Now, the problem is when I extruded the outer pipe, it kind of eats the helix pipe and they become 1 combined volume, instead of two different volumes. As a result, I can not do the rest of the meshing-simulation process because I have a useless geometry.

Could you tell me how to split the volume in Solidworks? (I know basic splitting but for this case I could not use it-it keeps asking a surface to use as a reference for split. It does not accept the surface of a feature to use as a referecene)

Not a Solidworks expert, but if this were DM, I would tell you to extrude with one part frozen so it doesn't merge them as it goes.

Perhaps in Solidworks you need to make sure that the materials are different or something like that.

Thanks.
I do not know what do you mean by 'frozen' ? Is ıt possible to freeze a part and then use it another feature that was created while it was frozen? I know suppress/unsuppress and it does not work. The part still merges.

When you create your second extrude, make sure that merge is deselected. That should give you 2 bodies in the single .prt file.

That works great. Thanks a lot.