BOUNDARY INTEGRAL ELEMENT METHOD FOR LINEAR DIFFUSION REACTION PROBLEMS WITH DISCONTINUOUS BOUNDARY-CONDITIONS

A numerical procedure based on the boundary integral element method has been implemented for the solution of the linear diffusion-reaction equation in two dimensions. In this method the dimensionality of the problem is reduced by one by choosing the modified zero-order Bessel function of the second kind as the weighting function. Thus the discretization of only the enclosing perimeter is needed for numerical computations using this method. Discontinuous boundary conditions and irregular shapes are easily handled by this technique. The method can be extended to three-dimensional problems with the associated benefits of reduction in dimensionality. A number of examples are presented to illustrate the method. One such case study presented is the calculation of catalyst effectiveness factor in trickle beds under conditions of partial wetting. The paper also presents the numerical and analytical investigation of the region near the singularity due to the presence of the discontinuous boundary condition.