rotated_ellipse

<< Click to Display Table of Contents >>

Navigation:  Sample Problems > Usage > Misc >

rotated_ellipse

Previous pageReturn to chapter overviewNext page

{ ROTATED_ELLIPSE.PDE

 

 This example shows the use of ROTATE to create a rotated

 ellipse. The selector MERGEDIST is used to allow fewer digits

 of accuracy in the positions of the points on the ellipse.

}

TITLE 'Electrostatic Potential and Electric Field'

 

VARIABLES V Q

 

SELECT mergedist = 0.01 ! merge imprecise points in ellipse

 

DEFINITIONS eps = 1

 

EQUATIONS

 V: div(eps*grad(V)) = 0       {potential equation}

 Q: div(grad(Q)/eps) = 0       {adjoint equation}

 

BOUNDARIES

REGION 1

  start(0,0)

  value(V) = 0 natural(Q) = tangential(grad(V))

  line to (3,0)

  natural(V)=0

  line to (3, 2.5)

  value(V) = 100 natural(Q) = tangential(grad(V))

  arc(center = 1.5, 2.5) angle= 180.

  natural(V)=0

  line to close

  ! embedded path will become an EXCLUDE :

  start( 2.08, 2.08)

  natural(V) = 0 natural(Q) = tangential(grad(V))

  arc(center = 1.5, 1.5 rotate= 45.) to ( 1.22, 1.78)

  arc(center = 1.5, 1.5 rotate= 45.) to ( 0.92, 0.92)

  arc(center = 1.5, 1.5 rotate= 45.) to ( 1.78, 1.22)

  arc(center = 1.5, 1.5 rotate= 45.) to ( 2.08, 2.08)

 

PLOTS

  grid(x,y)

  contour(V) as 'Potential'

  surface(V) as 'Potential'

  contour(Q) as 'Field Lines'

  vector(-dx(V),-dy(V)) as 'Electric Field'

 
END