[no subject]

["bhaskar bollapragada" <bhaskar_77@xxxxxxxxxxx>]

Dear Mr.David Meeker,

I tried to model a linear actuator based on lorentz law principle. I have done the simulation without current in the coil and plotted the flux density in perpendicular direction between the magnet and the coil air gap. The flux density is around 0.45T.I took this value and calculated the force experienced by the coil theoritically which is given by F=ILB

= 0.1A*22*10e-3 m*200*0.45T

the coil taken is with 200 turns and the length of the coil is 22mm as the depth of the yoke on which the coil is wound around is 7mm amd breadth is 4mm.

so I get a force of around 0.2N .

I simualted with current density of 1.176A/mm²(as the cross section of the coil designed is 17mm²) and calculated the force experienced by the coil using block integrals loretz force option and multiplied the obtained result with 7mm(which is the depth of coil) but I am getting the force as 0.1N.The difference is almost 50% where I have gone wrong can you suggest.I am sending the femm file as attachment.

thanking you,

your's faithfully,  


Bhaskar Bollapragada

Phone Mobile:0049-01795405408

Home :0049-40-55574008

Ebeling straße 1

wg 621d

Hamburg

Germany

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