ABSTRACT
This chapter presents methods to solve problems with three independent variables involving first-order differential equations and second-kind boundary conditions. Therefore, partial differential equations are involved. Mathematically, this class of cases can be summarized as second-kind boundary condition. The chapter considers the problem of a heating fluid at two-dimensional flow for which the solution is obtained by Laplace transform. A 3-D scheme for the problem of reacting fluid at 2-D flow is also presented in the chapter. Here, components A and B react and a constant mass rate of species A diffuses through the porous grid into the fluid. The solution by Laplace transform is presented for this condition.
