Bill Bulat
Ansys Employee
Hi,nSee if turning off pivot checking helps. To do this, use the PIVC,OFF command prior to the SOLVE command. I have yet to see a case in which disabling pivot checking causes an erroneous emag solution, so chances are very good it should be OK to do this.nStrictly speaking, the modeled representation of the moving electrically conductive domain (in your case the plate) is supposed to be continuous in the direction of motion for the velocity effect to be valid:nYour modeled representation of the plate appears to have a finite length. If you need it to remain so, try to find a way to validate the results you obtain (e.g., see if the induced eddy currents are normal to the plate boundaries). nAlso, depending of the velocity and electrical resistivity of the conductor, the mesh may need to be refined so that the resulting magnetic Reynold's number isn't too high:nnLastly, the nodal based MVP (magnetic vector potential) formulation used by legacy SOLID97 element type can produce erroneously calculated fields on material interfaces between domains that have very different magnetic permeabilities (e.g., iron and air). This is due to the fact that the MVP forces the tangential component of B to be continuous on the interface. Physically, there is a discontinuous jump in the tangential component of B at such an interface. The edge-flux formulation used by the new technology SOLID236/237 properly addresses the field at such interfaces. If the PM is Neodymium, then it has a permeability that is quite close to that of free space and the error might be acceptably small. If the permeability of the PM is high, you should probably consider using new technology SOLID236/237.nOh, one additional thing. When using the FMAGSUM command to get the plate force, the forces determined by the virtual displacement method are typically more accurate than those obtained using the Maxwell stress tensor. But more accurate than either of these (as long as the conductive body is not permeable, as is the case for Copper) is a summation of the Lorentz forces. You can select the plate elements and read in the x, y, and z components of FMAG into the element table (these should be the volumetrically distributed Lorentz forces in the plate at element centroids) and use the SSUM command to obtain total values for the selected elements.I hope this helps,Best,Bill