On the evaluation of nearly singular kernel integrals in boundary element analysis - Some improved formulations

The paper attempts to improve the efficiency of a general method developed previously for computing nearly singular kernel integrals. Three new formulations are presented by following an approach similar to that used in the previous method. Their numerical efficiency is compared with the previous method. The results indicate that these new formulations are substantially more efficient than the previous method. In particular, the new formulation in which the same sampling points for all n values are used is the most efficient. This new formulation remains highly efficient even when the field point is as close to the panel surface as 0.1 per cent of the panel diagonal.