Mechanical Engineering

From my knowledge on simulations, soft bodies with special properties like cheese are extremely difficult to replicate. Especially when introducing cracks, slicing or separation like you would with a cheese cutter, the problem is even harder. It's barely even solved in academia, and much less in commercial software like Solidworks I'm afraid.

Instead, I advise you to lean on a mechanical principle which is robust enough that you won't need simulations. If you describe the problem in more detail you may get helpful answers here!

If your cutting large blocks in to portions or sticks then a fairly simple way would be to use a cutting wire frame attached to a pneumatic ram. Obviously make sure guards/interlocks etc are in your design.

What a coincidence, I just did a pre-engineering study for a client that owns a cheese factory. We were looking at automating the whole cutting process starting from the block of cheeses all the way to square slices about 3 mm thick.

What can I help you with?

You should be super careful how you simulate cheese in SW. Cheese can be very "sticky" depending on the type of cheese you need to work with.

The mechanical properties of cheese can vary wildly depending on the type and even on the batch (of the same type).

Obviously, all surfaces in your design must be "food grade", which means that porosity should be as low as possible. For starters, all steel should be stainless steel 304. Some other types of SS can also be used, but sticking with SS 304 is your best bet if you are not familiar with the different alloys of SS.

All plastic belts, o-rings, etc. must be made of washable material made specifically for food.

Your design must be "wash down" proof as all cheese factories must be completely washed down at least once a day. The products used for wash down are mostly water and soap. But the soap is a special blend of chemicals that will disinfect every surface it is sprayed on. This is corrosive stuff, especially given that the equipment is generously spayed with the cleaner at least every day.

Avoid any surface that can hold water, like puddles. No standing water is acceptable anywhere, so ensure you have sufficient drain holes and angles everywhere to get rid of standing water.

For the cutting part, I know of three ways to cut cheese:

1) "Harping" is the same as wire cutting. Very simple design, but limited to fairly low speeds. Usually used for things like cutting blocks (what the cheese factory produces).

2) Ultrasonic blade. This is a blade that goes up and down very quickly while you push cheese under it. The ultrasonic part is to avoid cheese sticking to the blade. The max speed for this process is about 200 cuts per minute, and at this speed you need a very good design. Usually, 60 to 100 cuts per minute is the maximum.

3) Rotating blade. This process is extremely fast, but also very expensive.

You can see examples of these processes on Youtube.

Thank you for your insight.

Yes,I am mostly relying on research papers for mechanical properties and already done experiments.The properties like young's ,shear and bulk modulus ,I obtained them almost after a lot and lot of surfing and reading.But i Observed that there are no definite answers or values to objects like cheese.

I just didnt want to overengineer the machine as it would increase the production cost.

Thank you for the reply.

Yes i am using exactly that.I am using a 3 dimensional cutting method though.

So if you have any insights on pneumatics too ...it will be much appreciated

That is such a relief to know

How much do you think i should keep the porosity at?I will try that too.

And the machine that i am crying to design is not for mass production.

I did find out that there is no substitute to SS 304 in food industry for cutting.And everything that will touch the food needs to be either ss or an FDA approved plastic.

Is SW the right software to analyse this setup?I am going to use ANSYS though it will require same properties for input.

Also, can you give me an insight on the kind of pneumatics that i should use as i am going for cutting of semi hard to hard type of cheese.Like gouda or parmesan?It would be a huge help.I have been searching online and found out that 6 bar(0.6 MPa) pressure would be enough to cut gouda.I was thinking of using a compressor which would offer 8bar(0.8MPa) pressure for hard cheese like parmesan.

to get information on the physical properties of the cheese, you might contact a university that has a food engineering or agricultural engineering program. If they can't point you to some source material, they might be able to do measurements on the cheese and get you some information that you could put into a program like ANSYS. The trick is a lot of biological materials behave in non-Newtonian ways. once you have an idea of the forces and behavior, you could probably do a quick analysis to determine the behavior of the cheese via the different methods mentioned above. Speed and volume may also make a difference in choosing a method of cutting as some may not lend themselves to slow or high speeds. hope this helps