MODIFYING COMBUSTION KINETICS BY PHOTODISSOCIATION OF INHIBITORS

THE FEASABILITY OF IMPROVING COMBUSTION BY A NOVEL APPROACH IS EXAMINED. THIS ENTAILS MODIFYING REACTION KINETICS BY PHOTODISSOCIATION OF REACTION-INHIBITING CHEMICAL SPECIES TO REACTIVE RADICALS WHICH PARTICIPATE IN CHAIN-BRANCHING. THE CONCEPT WILL BE TESTED IN A SIMPLE, CLEVER EXPERIMENT IN WHICH THE EFFECT OF PHOTODISSOCIATION CAN BE UNAMBIGUOUSLY INVESTIGATED. FOR THIS PURPOSE THE PHOTO- DISSOCIATION OF THE METASTABLE HO2 RADICAL WAS SELECTED. IT IS WELL ACCEPTED BY COMBUSTION EXPERTS THAT THE SECOND EXPLOSION LIMIT OF HYDROGEN-OXYGEN MIXTURES IS ATTRIBUTED TO THREE BODY COLLISION H + O2 -> M HO2 + M. THIS REACTION BECOMES IMPORTANT AT HIGH PRESSURE AND EFFECTIVELY COMPETES WITH THE CHAINBRANCHING H + O2 -> OH + O. THUS PHOTODISSOCIATION OF HO2 TO OH + O WILL SHIFT THE KINETICS IN FAVOR OF CHAIN-BRANCHING, ENHANCING REACTIVITY AND RESULTING IN AN EXTENSION OF THE EXPLOSION PENINSULA NEAR THE SECOND LIMIT. THIS WILL BE TESTED BY PREPARING STATIC HYDROGEN-OXYGEN MIXTURES AT THE NON- EXPLOSIVE REGION NEAR THE SECOND LIMIT. THE MIXTURE WILL THEN BE IRRADIATED WITH ULTRAVIOLET LIGHT AT A WAVELENGTH CAPABLE OF SELECTIVELY DISSOCIATING HO2 TO THE CHAIN- CARRYING O AND OH RADICALS. IF THE MIXTURE EXPLODES UNDER IRRADIATION AT THESE NORMALLY NON-EXPLOSIVE CONDITIONS, THE INNOVATION HAVE BEEN EXPERIMENTALLY CONFIRMED. THE G GROUNDWORK WILL THEN HAVE BEEN LAID FOR PHASE II RESEARCH ONMODIFYING COMBUSTION KINETICS IN OTHER FUEL-AIR MIXTURES BY FIRST IDENTIFYING OTHER INHIBITING SPECIES AND THEN EXAMINING THE AVAILABILTY AND AFFECTIVENESS OF PHOTO- DISSOCIATING THEM TO RADICALS UNDER CONDITIONS APPROPRIATE TO ENERGY CONVERSION DEVICES.