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Calculating the volume of a cavity inside an assembly

Hi, I'm a mechanical engineering student and I've been asked to create a piston on solidworks. I created the whole assembly by building all the required parts (piston_rod, piston_cylinder, piston_right_flange, etc...).

Now I've been asked to calculate the volume of the oil inside the piston at all times. I have tried some things but haven't been able to find a way to do the calculations in a timely fashion. Is there any tool or feature that I don't know about and that could do the job?

Reply to
mrcocky
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The first and easiest way for me, as I have totally irregular complicated cavity volumes is to do the following:

  1. Create a new assembly file "ChamberForVolume.SLDASM"
  2. Put in the Cylinder as the first part
  3. Add in the Piston as the second part (with a configuration which increases the OD of the Piston at the appropriate point to cause it to touch/interfere with the wall of the cylinder)
  4. Select the Cylinder in the Feature Manager & choose Edit function/icon
  5. Select the Piston & go to the command for Join (this will combine both parts into one on the original Cylinder file
  6. Deselect the Edit function in the assembly file.
  7. Create a new assembly file "CylinderVolCut.SLDASM"
  8. Make a solid "block" bigger than the now closed Cylinder & add it to the above #7 assembly file
  9. Add the closed Cylinder (pick the right config) to the #7 assembly
  10. Select the "block" in the #7 assembly and choose the Edit function/icon
  11. This time choose the function "Cavity" with the Cylinder selected and then you pick the right volume to save and use the Mass function to tell you the volume.

I hope my memory was good enought to do this without looking at SolidWorks (I have done this hundreds of times).

Good Luck - Bo

snipped-for-privacy@gmail.com wrote:

Reply to
Bo

Now, if you need to calculate the change in volume for any different stroke, you can use Excel to set up the incremental volume change for any simple stroke change, so you can calculate and/or chart the volume at various strokes.

Bo

snipped-for-privacy@gmail.com wrote:

Reply to
Bo

Is the goal to be able to manually position the cylinder piston anywhere and then query for the enclosed volume? If so, then a solution might be to create a part in the context of the assy that is the cylinder volume. This can be just a simple cylinder, if that's all that's required, or it could be a revolved profile that also takes into account the volume that will be around the top of the piston above the top ring - your choice on how accurate you need to be. Then when you need the volume, just highlight that part in the tree and run mass properties.

WT

Reply to
Wayne Tiffany

If you draw a part (that is the volume) in the assembly level using the pison and cyclinder wall; you can then move the piston in the assembly, then regenerate and querry the volume of the "volume" at any piston location. -Matt

Wayne Tiffany wrote:

Reply to
Matt Johnson

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