Abstract: An aircraft engine includes an aircraft engine controller configured to detect an actual peak exhaust gas temperature of a cylinder assembly. The aircraft engine controller detects an intersection between a first function representing a relationship between a set of rich exhaust gas temperature signals and a corresponding set of rich fuel-air ratio values and a second function representing a relationship between a set of lean exhaust gas temperature signals and a set of lean fuel-air ratio values. Based upon the intersection between the first and second functions, the engine controller detects an actual peak fuel-air ratio value for the cylinder assembly and can determine if a correction in the fuel-air ratio of a fuel-air mixture provided to the cylinder assembly is required. Accordingly, the engine controller provides each cylinder assembly of the aircraft engine with an accurate fuel-air mixture to allow for operation of the engine with optimal fuel economy.

Abstract: An aircraft engine includes an aircraft engine controller configured to detect an actual peak exhaust gas temperature of a cylinder assembly. The aircraft engine controller detects an intersection between a first function representing a relationship between a set of rich exhaust gas temperature signals and a corresponding set of rich fuel-air ratio values and a second function representing a relationship between a set of lean exhaust gas temperature signals and a set of lean fuel-air ratio values. Based upon the intersection between the first and second functions, the engine controller detects an actual peak fuel-air ratio value for the cylinder assembly and can determine if a correction in the fuel-air ratio of a fuel-air mixture provided to the cylinder assembly is required. Accordingly, the engine controller provides each cylinder assembly of the aircraft engine with an accurate fuel-air mixture to allow for operation of the engine with optimal fuel economy.

Abstract: Strongly exothermic, catalytically induced or promoted chemical reactions, e.g. the production of methane by the reaction of hydrogen with carbon oxides, are carried out by passing the reactants through an isothermically operated reactor in addition to an adiabatic reactor.

Abstract: Highly exothermic continuous chemical reactions such as the methanization of carbon oxides are cooled by indirect heat exchange with a liquid coolant such as water, thereby converting at least some of the liquid to a vapor such as steam. When the reaction temperature, because of operational difficulties or the like, exceeds the design temperature of the reaction, said vapor such as steam is passed into the reaction chamber. In this way, the reaction stream is cooled as well as diluted; in addition, since the vapor is preferably selected to be a reaction product, the extent and rate of the exothermic reaction are diminished.

Abstract: In a process for the production of olefins in two stages wherein, in the first stage, heavy petroleum fractions are hydrogenated in the presence of hydrogen and a hydrogenation catalyst and, in the second stage, the thus-hydrogenated fractions are subjected to thermal cracking the presence of steam, the improvement which comprises employing as the hydrogenation catalyst a zeolite of the faujasite structure combined with elements from Groups VIB, VIIB and VIII of the periodic table of the elements, wherein the alkali component of the zeolite is exchanged at least partially for ammonium, hydronium, alkaline earth and/or rare earth ions, and the elements are present in a metallic, ionic, oxidic and/or sulfidic form.