Tungsten Alloy for Turbo Engines
Tungsten alloy turbo engines are the heat engine which is conditioned by their maximum intake temperature, and turbo engines are limited by the behavior of the constituent materials of the articles that are most exposed to heat and constraints.
Why Choose Tungsten Alloy Turbo Engines?
Concerns for environmental protection have led designers of aviation tungsten heavy alloy turbo engine to search for means to reduce the proportion of pollutants in the exhaust gases of the engines. It is known that the principal problems in the matter of pollution of aviation tungsten alloy turbo engines are, on the one hand, the emission of carbon monoxide, of hydrocarbons, and of various unburnt residues during operation on the ground and, on the other hand, the emission of nitrogen oxides and of particles during take-off and during cruising at altitude. Therefore, tungsten alloy turbo engines are increasingly accepted by public.
Tungsten heavy alloy turbo engine is generally of optimized rating for take-off or near take-off operation. This signifies that, in the primary zone of the combustion chamber, a fraction of the air flow of the compressor is introduced so that, with the injected fuel, the fuel-air mixture in this zone would be essentially stoichiometric in turbo engines. Under these conditions, due to the levels of temperature and high pressures, as complete as possible a combustion is obtained, combustion yields greater than 0.99 are attained, the speeds of the chemical reaction being optimum for these stoichimoetric mixtures.
The first two times can be considered negligible at high ratings because of the pressures which are attained, but it is not so at low ratings. In fact, in order to increase the speed of the vaporization of the fuel, it must be transformed into fine droplets, which, in normal operation, is easily realized by the conventional mechanical atomizing injector, but the performance which is obtained in the lower ratings is poor. This is due to the fact that, if the fuel is well divided into droplets, these are poorly mixed with air in the primary zone and local zones would appear which have a richness which is too high. In the end, it would be necessary that each droplet would have around it the quantity of gas necessary for its vaporization and for its combustion, i.e., a quantity of gas which results in a stoichiometric mixture with the oxygen molecules after complete vaporization. In order to accomplish this, systems such as aerodynamic injection have been proposed. Aerodynamic type injectors generally comprise whirling, or swirled vanes through which the air from the compressor is introduced, which serves to atomize the fuel. An air/fuel pre-mixture is thus obtained. All of these solutions, which allow an improvement in the combustion yield have, however, a maximum efficiency only for values sufficient for the pressures and temperatures of the air at the chamber inlet. All of these factors are advantageous for a reduction of the reaction times and could lead to a reduction of the length of the combustion chamber for tungsten heavy alloy turbo engine and thus to a limitation of the dwell time of the gases in the latter. In the whole working environment, material of heat-resistance is required, therefore, tungsten heavy alloy for turbo engine is widely used for that.
A first objective of tungsten heavy alloy turbo engine is to provide a novel solution to the problem of low operating combustion for a chamber which includes aerodynamic type or pre-atomization injectors, which are mounted in the base of the chamber. In fact, in the case of a conventional chamber of tungsten heavy alloy turbo engine, which is arranged to provide a stoichiometric mixture at take-off, about one-third of the air flow necessary for the combustion of tungsten alloy turbo engine is introduced in the injection system and two-thirds by the primary orifices.
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