Description

EX_MAGNETOSTATICS5 Magnetic field test model.

[ FEA, OUT ] = EX_MAGNETOSTATICS5( VARARGIN ) Magnetic field test model.

Accepts the following property/value pairs.

Input       Value/{Default}        Description
-----------------------------------------------------------------------------------
sfun        string {sflag2}        Shape function for pressure
hmax        scalar {0.1}           Grid size
iplot       scalar 0/{1}           Plot solution (=1)
                                                                                  .
Output      Value/(Size)           Description
-----------------------------------------------------------------------------------
fea         struct                 Problem definition struct
out         struct                 Output struct

Code listing

 cOptDef = { 'sfun',     'sflag2';
             'hmax',     0.1;
             'iplot',    1;
             'tol',      1e-2;
             'fid',      1 };
 [got,opt] = parseopt(cOptDef,varargin{:});
 fid       = opt.fid;


% Geometry and grid generation.
 fea.sdim = { 'x' 'y' };
 fea.grid = rectgrid( round(1/opt.hmax) );
 fea.grid.s( selcells(fea,'y<=(0.5+sqrt(eps))') ) = 2;


% Problem definition.
 fea = addphys( fea, @magnetostatics );
 fea.phys.ms.eqn.coef{3,end} = { 1 0 };
 fea.phys.ms.eqn.coef{4,end} = { 0 1 };
 fea.phys.ms.sfun = { opt.sfun };


% Parse and solve problem.
 fea       = parsephys( fea );
 fea       = parseprob( fea );
 fea.sol.u = solvestat( fea, 'icub', 2, 'fid', opt.fid );   % Call to stationary solver.


% Postprocessing.
 if( opt.iplot>0 )
   figure
   postplot( fea, 'surfexpr', fea.phys.ms.eqn.vars{2,2}, ...
             'isoexpr', fea.phys.ms.eqn.vars{2,2}, 'isolev', 25, ...
             'arrowexpr', fea.phys.ms.eqn.vars{8,2}, 'arrowcolor', 'w', 'arrowspacing', [45 30] )
   title( 'Magnetic field' )
 end


% Error checking.
 Az1  = intsubd( fea.phys.ms.eqn.vars{1,2}, fea, 1 );
 Az2  = intsubd( fea.phys.ms.eqn.vars{1,2}, fea, 2 );
 Mf1  = intsubd( fea.phys.ms.eqn.vars{2,2}, fea, 1 );
 Mf2  = intsubd( fea.phys.ms.eqn.vars{2,2}, fea, 2 );
 Scb1 = intbdr(  fea.phys.ms.bdr.vars{2,2}, fea, 1 );
 Scb2 = intbdr(  fea.phys.ms.bdr.vars{2,2}, fea, 2 );
 Scb3 = intbdr(  fea.phys.ms.bdr.vars{2,2}, fea, 3 );
 Scb4 = intbdr(  fea.phys.ms.bdr.vars{2,2}, fea, 4 );
 out.err = [ abs(Az1+3.178289e-8)/3.178289e-8 ;
             abs(Az2+3.178289e-8)/3.178289e-8 ;
             abs(Mf1-0.389419)/0.389419 ;
             abs(Mf2-0.520161)/0.520161 ;
             abs(Scb1-0.16233)/0.16233 ;
             abs(Scb2-0.836552)/0.836552 ;
             abs(Scb3+0.83767)/0.83767 ;
             abs(Scb4+0.16343)/0.16343 ];
 out.pass = all( out.err < opt.tol );


 if ( nargout==0 )
   clear fea out
 end