most recent 30 from http://mathoverflow.net 2013-05-24T14:52:57Z http://mathoverflow.net/feeds/question/25494 http://www.creativecommons.org/licenses/by-nc/2.5/rdf http://mathoverflow.net/questions/25494/dirichlet-boundary-conditions Marios Karaoulis 2010-05-21T15:13:17Z 2010-05-26T16:45:33Z

<p>Hi, I am using the finite element method to solve current flow in earth. So far my problem is this Consider a square,</p> <pre><code> (air) ----(1)------ (air-ground suraface) | | </code></pre> <p>|(ground) (2).................... (3) (ground).</p> <pre><code> | | | | -----(4)----- (ground) </code></pre> <p>In (1) (air-ground) I use the homogeneous Neumann conditions, (which the algorithm takes automatic account for).</p> <p>I make (2)(3)(4) quote large so I apply homogeneous dirichlet conditions. Current is injecting from some points in (1).</p> <p>I want to modify it so now (2) (3) and (4) be also air. Obviously now homogeneous dirichlet is not the case. </p> <p>I am thinking two options. 1) If I don’t use dirichlet conditions, then neuman wouldn’t be calculated automatically? Do I need something more? 2) Shall I use any other boundary conditions is (2)(3)(4)?</p>