Numerical Solution for the Catalytic Pellet BVP

Here we treat the more realistic case that the right-hand side of equation (5.53) is nonlinear. Such a nonlinearity is generally introduced by a nonconstant reaction rate that depends upon the temperature as exemplified by the Arrhenius dependence (2.1). 

First we study a model made up of one second-order BVP, followed by a more advanced model that relies on two coupled second-order BVPs. 

---