The Investigation Of The Operational Characteristics Of Air Atomization Injector In The Gas Turbine And The Numerical Simulation Of The Flame Tube Dome

The current situation and development of injectors used in the aero engine and gas turbine at home and abroad is comprehensively examined in this paper. On the basis of home gas turbine studying and practical application, some characteristics of fuel injector GE4319 in the ground gas turbine have been studied here. Phase Doppler particle Analyzer/ Laser Poppler Velocimeter system(PDPA/LDV) is employed to investigate the air atomizing characters of the injector experimentally. fuel-supplying performances, spray cone angle changing characters, droplet size and its distributions law have been obtained. By mean of much testing and analysis, the following conclusions have been obtained: the fuel flow of this injector increases along with the operating pressure increasing, and the increasing trend decreases when the pressure increases to some extent value. Spray cone angle is basically independent on fuel-supplying pressure changing, but decreases along with the gas-supplying pressure increasing and when air pressure increases to 0.3MPa, the spray cone angle is decreased about 8°. Sauter mean diameter SMD is almost not influenced by the fuel-supplying pressure change when gas is supplied, but decreases along with the fuel-supplying pressure increasing and the decreasing value of SMD is about (15-20)μm, the droplet size SMD tends to be a constant when the gas-supplying pressure increases to some extent value. For studying of the interaction between the air atomization injector and the airflow structure in the dome of the flame tube of the combustor, the numerical simulation of the combustion chamber under the middling operation condition has been made also in this paper, these important characters, such as temperature field, the velocity field of the flame tube dome, fuel droplet trace, its resident time as well as spray discharge stroke and so on, and airstream structures under the interaction due to the fuel spray and airflow entered into flame tube dome have been provided. These results have given reliable references and basic data for the combustor and injector design, improvement, in particular, for the development of the new air atomization injector, hybrid injector, and comprehensive design of the flame dome-injector, and have some import application value.