High Temperature Superconducting Magnetic Levitation

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7.6 Three-dimensional modeling and simulations Ë 241

Fig. 7.16:Geometrical modeling of the 3D simulation of
the HTS Maglev system.

described in Fig. 7.16. The virtual conductivity of the HTSC is calculated by


1
휎sc

=|Esc|
|Jsc|

, (7.51)


whereEscandJscare the electric field and current density of the HTSC, respectively.
According to theE-Jexponent power law (see Eq. 7.14), the expression to calculate the
conductivity is


1
휎sc

=|Esc|
|Jsc|

=Ec0
Jc

œ|Jsc|
Jc




n− 1

. (7.52)


Based on Ampère’s law [see Eq. (7.1)], we have


Jsc,xx̂+Jsc,yŷ+Jsc,zẑ=¤휕Hz
휕y


휕Hy
휕Hz


휕Hy
휕Hz

¥x̂+œ휕Hx
휕z

−휕Hz
휕x

ŷ


휕Hy
휕x

−휕Hx
휕y

¥ẑ. (7.53)

Therefore, the three components of the supercurrent can be expressed in terms of the
magnetic field as follows:


. (^66)
(^666)
(^66)



(^66)
(^666)
(^66)
F
Jsc,x=
휕Hz
휕y −
휕Hy
휕z,
Jsc,y=휕Hx
휕z
−휕Hz
휕x



,


Jsc,z=

휕Hy
휕x

−휕Hx
휕y

.


(7.54)


The anisotropic feature of the critical current density in the HTSC is considered in
the 3D modeling by assuming that the critical current density along thec-axisJcc
is one third of the critical current density within thea-bplaneJabc [47]. In order

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