ERROR ANALYSIS IN APPLYING A BOUNDARY-ELEMENT METHOD FOR 3-DIMENSIONAL STEADY-STATE POTENTIAL PROBLEMS

The boundary element method (BEM) has been applied to the case of thre e-dimensional steady state heat flow with no internal heat generation. The edge and corner effects and the near surface difficulties due to singular integral kernels of BEM are considered. Certain existing meth ods to overcome these difficulties have been implemented and tested. A n algorithm is proposed which considers floating temporary nodes and l ocal refinements of the mesh for interior points close to the boundary . The effects of the different methods of reducing the error are studi ed in the case of temperature distribution in a cube. The severity of the various errors increases with the coarsening of the mesh. The prop osed method, however, is found to solve the near surface problems very effectively, even in the case of a very coarse mesh with negligibly s mall excess processing time.