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<p>Hello Everyone,</p>
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<p>since a couple of days, I am comparing the solution of GetDP with the analytical solution of a simple earthing arrangement.</p>
<p>There are two hemispheres, both have their origin in point (1)={0,0,0,lc1}, the earth electrode (inner hemisphere) has a radius of r0 = 1 m, the reference ground (outer hemisphere) has a radius of r1 = 200 m.</p>
<p>Between these hemispheres a current of -10 kA flows, the potential of the inner hemisphere is set to 0 V (yes, really). The soil resistivity is set to rho = 30 Ohm*m.</p>
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<p>The voltage at the outer hemisphere can be calculated as follows: U = I * rho / 2 / Pi * ( 1/r0 – 1/r1 ) = 47508 V</p>
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<p>With the attached files, I get a result from GetDP of U = 44666 V</p>
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<p>Is it possible that there’s something wrong with the meshing? I think the deviation is too big to explain it with the different "solving procedure"...</p>
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<p>Greetings,</p>
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<p>Jochen</p>
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