Calculating the force exerted on structure by two large permanent magnets

[Lewy1234]

I am a mechanical engineering student so don't have experience in specifying magnets and or using them. So its out of my comfort zone.

I currently have a U shaped structure holding two large permanent magnets apart at either end. The magnets will need to be 200x200x40 in size and the gap is going to about 250mm. How do i calculate the force that will be exerted on the structure given typical specs from suppliers. What specs will i need and formulae?

I've had a look at literature and it seems to have been reading and derived the the classical formulae for force between magnets.

F=6k(q_m*q_m'*L²)/r² and i Know that M_m = q_mL

Is this the correct formula to use? If soo, I can't seem to find the variables to fit into the equation from typical data given from magnet suppliers.

 

[Vailanor]

Any help would be greatly appreciated. The formula you have provided is a general equation for calculating the force between two magnets. However, in order to use it you will need to calculate the magnetic field strength at the gap distance and the magnetic flux density at the gap distance. Both of these values are typically provided by magnet suppliers. You will also need to know the magnetic dipole moment of each magnet, which should also be provided. Once you have these values, you can then plug them into the formula to get the force.