Next: Potential Problems
Up: Magnetohydrodynamics MHD
Previous: Nonpotential current flowing inside
You must know the MHD equations.

(4.17) 

(4.18) 

(4.19) 

(4.20) 

(4.21) 

(4.22) 
and an energy equation.
Simplifications to the MHD equations include looking for steady, static
equilibrium solutions that satisfy force balance so that the equation of motion
reduces to

(4.23) 
If gravitational effects are negligible, then we have

(4.24) 
and finally, if the pressure gradient term is negligible (meaning that the
gas pressure is much smaller than the magnetic pressure
, the
magnetic field is called forcefree and

(4.25) 
Next: Potential Problems
Up: Magnetohydrodynamics MHD
Previous: Nonpotential current flowing inside
Prof. Alan Hood
20001106