MODIFICATION AND IMPROVEMENT OF SOFTWARE FOR MODELING MULTI DIMENSIONAL REACTION FUEL FLOW

MODIFICATIONS OF EXISTING SOFTWARE EMPLOYED IN THE NUMERICAL MODELING OF MULTIDIMENSIONAL REACTING FUEL FLOWS ARE PROPOSED WHICH WOULD IMPROVE THE COMPUTATIONAL EFFICIENCY AND ROBUSTNESS OF SUCH METHODS AND ALLOW THE INCLUSION OF A MORE DETAILED REPRESENTATION OF THE CHEMICAL AND PHYSICAL PROCESSES INVOLVED. PRELIMINARY MODIFICATIONS WOULD PRESERVE THE GRIDDING AND DISCRETIZATION OF EXISTING CODES WHILE INCORPORATING THE FULL CHEMICAL KINETIC MECHANISM OF THE FLAME, AND REPLACING THE SOLUTION ALGORITHM FOR THE NONLINEAR DISCRETE SYSTEM WITH A MORE IMPLICIT VERSION EMPLOYING ROBUST VARIATIONS OF NEWTON'S METHOD FOR BETTER CONVERGENCE PROPERTIES. A SUBSTANTIAL NUMBER OF THE MODULES TO BE INCORPORATED ALREADY EXIST "IN HOUSE" AND HAVE BEEN SUCCESSFULLY USED ON ONE-DIMENSIONAL FULL CHEMISTRY PROBLEMS AND ON TWO-DIMENSIONAL IDEALIZED CHEMISTRY PROBLEMS. RESEARCH COMPARING THE EFFICIENCY OF VARIOUS SOLUTION ALGORITHMS FOR HIGHER-DIMENSIONAL FULL CHEMISTRY FLAMES IS STILL NEEDED BECAUSE OF THE TREMENDOUS NUMBER OF UNKNOWNS INVOLVED IN THE DISCRETIZATION. SUCH COMPARISONS WILL BE UNDERTAKEN UNDER PHASE I ON AN AXIALLY SYMMETRIC LAMINAR DIFFUSION FLAME. FURTHER MODIFICATIONS ARE PROPOSED CONCERNING THE COMPUTATIONAL GRID OVER WHICH THE SOLUTION IS DEFINED, WHICH WOULD ALLOW MORE ACCURATE AND MORE PHENOMENOLOGICALLY CORRECT MODELING IN PRACTICAL COMBUSTOR GEOMETRY AND IN TURBULENT FLOW.