MORE ON OBLIQUE AND MIXED, SECOND DERIVATIVE BOUNDARY VALUE PROBLEMS

The method of the authors to solve elliptic boundary value problems with oblique and mixed, second derivative boundary conditions by decomposition into a self-adjoint first order system has been extended to situations in which first order chemical reaction is included in the differential equation and the boundary condition. This extension is indeed non-trivial and is applicable to a large variety of chemical engineering problems. The boundary conditions feature coefficients that are subject to a constraint for a self-adjoint formalism to accrue but one that is also imposed by the physics in the entire parameter space.