A vector field 
satisfying the vector identity
 |
where 
is the cross product and 
is the curl is said to be a
Beltrami field.
Beltrami Field
See also
Divergenceless Field, Irrotational Field, Solenoidal FieldExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Beltrami Field." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/BeltramiField.html