The capacity of burners for combustion chambers with reduced nitrogen oxide content in combustion products of the NK-16ST gas turbine engine

The article presents the designs of several variants of combustion chambers for the NK-16ST engine. The combustion chamber designs are made within the framework of known concepts of low-emission fuel combustion to reduce nitrogen oxide emissions. A serial combustion chamber with a stepped air supply along the length of the flame tube is considered. A combustion chamber with a reduced volume of the flame tube and a two-zone combustion chamber, as well as a combustion chamber with preliminary preparation of the fuel-air mixture in the burner device are considered. The features of burner devices of these combustion chambers are considered. For a serial combustion chamber, the burner device contains a nozzle, a swirler and a diffuser nozzle attachment. For a shortened combustion chamber, a confuser nozzle attachment is used. A two-zone combustion chamber contains two types of burner devices: diffusion for the duty zone and with preliminary mixing for the main zone. The combustion chamber with preliminary preparation of the fuel-air mixture contains a dual-circuit burner device with hollow blades and a central nozzle, which allows for regulation of fuel consumption along the circuits to ensure the required level of toxic emissions in the corresponding engine operating modes. The paper also provides a description of the bench equipment for purging burner devices, on which tests were conducted to determine their flow characteristics. The parameter of throughput, which is determined for each burner device, is derived. A description is given of the test bench equipment for purging combustion chambers, on which tests were carried out to determine pressure losses on the walls of combustion chamber fire tubes and total pressure losses in the combustion chamber under various inlet conditions for air velocity. A calculation and experimental method for determining the excess air coefficient at the outlet of the burner devices is presented. It is determined that in the combustion chambers under consideration, there is a tendency for the fuel-air mixture to become leaner at the outlet of the burner device. This ensures a reduction in nitrogen oxide emissions. Regulation of fuel consumption in the corresponding combustion chamber zones allows for an optimal level of emissions in various engine operating modes.