Re: four values for Maxwell force??

["David Meeker" <dmeeker@xxxxxxxx>]

--- In femm@xxxxxxxxxxxxxxx, "ahmad_m_eid" <ahmad_m_eid@xxxx> wrote:
> Dear all
> 
> I have a small problem, I think it is discussed before.
> When I calculate the force by line integral of maxwell stress tensor,
> I get four values for it { 0 0 values3 0}
> although I use magnetostatic problems (frequency = 0)
> this "values3" in the table of line integral corresponds to(page 52):
> 3 Stress Tensor Force DC r/x force DC y/z force 2x r/x
> force 2x y/z force.
> 
> So, I get "2x r/x force" although I use axisymmetric problems i.e.
> force in z-direction only.
> 
> 1- I need an explanations for my problem.
> 2- What does 2x force mean? i.e. the required force will be this value
> or divided by 2?
> 
> any explanation is welcomed.
> 
> ahmad

Each of these entries is potentially a complex value, so the first two
results are "DC r/x force", the third and fourth are real and
imaginagry for "DC y/z force", and so on. Since you have a
magnetostatic, axisymmetric problem, the only non-zero component is
the real part of the z-directed force, which is the third value
returned from the call. The "2x" forces are for AC problems, where
you get forces that are a combination of a DC force and a force at
twice the drive frequency.

Dave.
--
David Meeker
dmeeker@xxxxxxxx