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Test2d18, 18th 'benchmark test' data file for CPO2D

Field penetration through a flat mesh of parallel flat strips.

The following data were obtained when the memory and speed of PC's was much more limited than at present, so the available number of segments was small and the requested inaccuracies were fairly high to give a quick demonstration.

One of a set of files:

test2d18.dat: Field penetration through a flat mesh of flat strips.

xmpl2d19.dat: Field penetration through a cylindrical mesh of round wires.

xmpl2d20.dat: Field penetration through a flat mesh of round wires.

xmpl3d23.dat: Field and potential penetration through a flat mesh of crossed round wires.

xmpl3d29.dat: Field and potential penetration through a flat mesh of crossed flat wires.

The mesh is composed of 20 parallel strips (in planar symmetry) of width w=0.1, spaced by s=1.0 (between centres). The mesh is at potential 0 and is enclosed by a box that has end potentials of 0 at z=-10 and +10 at z=+10.

To improve the simulation the sides of the box are given the potential vm at z=0, where vm is the mean potential in the plane of the mesh (and where vm is determined by the program, so some iterating is required here). The sides of the box at z<0 and z>0 are given uniform potential gradients (again by adding vm).

For further details see the papers:

Short and long range penetration of fields and potentials through meshes, grids or gauzes, by F H Read, N J Bowring, P D Bullivant and R R A Ward Nucl. Instr. Meth. A427, 363-367 (1999).

Penetration of electrostatic fields and potentials through meshes, grids or gauzes, by F H Read, N J Bowring, P D Bullivant and R R A Ward, Rev. Sci. Instrum. 69, 2000-2006 (1998).

The following quantities are obtained:

(1) vm = the average potential at z = 0,

(2) vc = the potential at the centre of the mesh (that is, at x=0, z=0)

(3) ec = the field at the centre of the mesh.

All these values are extrapolated to an infinite number of segments (see below).

Results:

-extrapolated with 1/N**1.75

A program is available at the end of the data file for deducing the potentials and fields of the mesh.