What Is Turbine Propulsion?

It refers to a thruster that the nozzle can deflect in different directions to generate thrust in different directions. The aircraft using thrust vector technology uses the tail nozzle to deflect and uses the thrust generated by the engine to obtain additional control torque to achieve the attitude change control of the aircraft. Its outstanding feature is that the control torque is closely related to the engine, and is not affected by the attitude of the aircraft itself. For airplanes that do not use thrust vector technology, the jets of the engine are coincident with the axis of the aircraft, and the generated thrust is also forward along the axis. In this case, the thrust of the propeller is only used to overcome the resistance to the aircraft and provide the aircraft. Acceleration. Therefore, the vector thruster can ensure that the maneuvering of the aircraft is controlled by the additional steering torque provided by the thrust vector when the control rudder surface is nearly ineffective when the aircraft is flying at low speed and high angle of attack.

Turbofan 10 / 10A is a three-stage fan, nine-stage rectifier, one-stage high-voltage, one-stage low-voltage with a total of twelve stages, and a single-stage high-efficiency high-power high-low-pressure turbine, so-called 3 + 9 + 1 + 1 structure. High thrust, high thrust-to-weight ratio, low bypass ratio, advanced engine ^[1]

Looking back on the past 20 years of ups and downs, this pass, which was exchanged for wisdom and confidence by the vast number of researchers who did not humiliate the mission, not only glorified and honed, but also bitter and tragic. Before the 1990s, the aviation engine test bench of the First Aviation Power Station was very rude. Every time a test was started, the roaring sound was deafening, and it could be heard several miles away. The participants had to cover their ears with cotton balls. Despite this, the roar was unbearable during the afterburner test, and the strong noise can be imagined to stimulate the body. Those test drivers who experienced that kind of environment that year suffered from heart disease and eardrum perforations, but they never complained. It is also with these old aviation people that our aviation engine business can grow and develop.

The vast number of researchers participating in Taihang Engine have worked hard to overcome difficulties and overcome dozens of major technical keys. In 2003, the development of the "Taihang" engine entered a decisive battle. There are still many gaps in the understanding and grasp of the law of engine development, and there are some problems in quality management and work style, which have caused the development work to be in trouble for several times. It has withstood two major tests successively: one was the rupture of the fourth-stage disc of the high-pressure compressor during the engine test; the second was during the high-altitude platform simulation test and adjustment test flight, and some technical problems were exposed, such as high-altitude The small-speed engine accelerates slowly. During the test flight of the aircraft from late August to early September 2003, five special landings occurred on five landings. In the summer of 2004, during the required test flight of the Taihang engine, the engine stopped in the air. Although it finally returned safely, the development of the Taihang engine became passive. The 606 Institute worked with experts inside and outside the industry to analyze troubleshooting countermeasures, and did a good job in fault research and fault analysis. It completed 17 fault calculations, studies, and analysis reports, and finally resumed the test flight of the Taihang engine. Various technical problems encountered during test flight such as ground surging, abnormal sounds in the air, abnormal test temperature, and early release of small hair ^{[3] were} solved.

In the trial production of the engine, China First Airlines creatively learned and applied advanced foreign experience, broke the management model of one plant and one machine in the past, and took advantage of various domestic professional advantages. A number of companies formed a national joint team to collaborate in tackling key problems and successfully applied hundreds of New materials, new processes. Engine materials have approached or reached international advanced levels. Advanced new materials account for more than 50% of the weight of the whole machine. Including advanced titanium alloys, advanced high-temperature alloys, and high-strength-high-temperature resin-based composite materials used for the first time on domestic engines.

New technologies used in the development of Taihang engines are:

1) The three-stage fan is a transonic aerodynamic design with variable intake camber guide vanes. It adopts a cantilever support without intake camber guide vanes. The super-plastic diffuser intake casing is a domestic design technology. A new breakthrough
2) The two-stage low-pressure turbine is a three-dimensional aerodynamic design with composite tilt and torsion. The two-stage guide vanes of the low-pressure turbine are hollow and triple integral integral casting structures, which are opposed to the high-pressure turbine.
3) Taihang's hollow blades, 606 of the best domestic experts in design, materials, technology, processing, testing, etc., form a "national team". After 8 years of intensive research and testing, they finally mastered this reputation The cutting-edge technology of the "Pearl on the Crown" of modern aviation engines. Drawing on the international advanced film cooling technology, boldly adopting composite air-cooled hollow turbine blades. It not only includes advanced design technology, high temperature material technology, but also directional solidification technology, precision casting technology, five-axis CNC drilling technology, abrasive grain finishing technology, non-destructive testing technology, cooling test technology, and high temperature coating technology.
4) "Taihang" engine composite material culvert box is the first application of composite technology in domestic aviation engines. It is the fourth generation of foreign engine technology, which fills the gap of domestic aero engine technology; the composite material culvert box is 30% lighter than the titanium plate welded structure culvert box, and has higher specific strength, higher specific stiffness and longer fatigue life. Longer and more resistant to corrosion.
5) Afterburner is of parallel intake type, with wide working range, light weight, and small fluid loss. It adopts the divisional partial pressure oil supply scheme to ensure reliable ignition and stability in the engine working envelope;
6) For the first time, the fourth-stage and the second-stage high-pressure gas-static stator blades have achieved the cold rolling of superalloy blades for the first time in China. The successfully developed GH4169 alloy grade IV to grade static stator blade cold rolling has filled the blank of domestic high temperature alloy blade cold rolling technology. The research was completed at the end of December 2004, and it is in a leading position in the world. However, the GH4169 alloy compressor and turbine discs still have a small margin of performance. In some cases, the performance and organization of the discs cannot meet the standard requirements; new processes and structures need continuous improvement.
7) The tail nozzle is designed with a stepless adjustable convergence diffusion nozzle throughout the process, which fills the gap in China. However, the average qualified rate of precision castings with expansion nozzles is only 54%, which needs to be further improved.
8) Taihang "aero-engine turbine rear case electron beam welding, impeccable in terms of process arrangement and parts delivery quality.
9) Applying nano-zirconia technology to thermal barrier coating, putting a protective clothing with excellent performance and stability on the Taihang engine high-pressure turbine guide vanes and low-pressure first and second-stage guide vanes, reaching the world's thermal barrier At the forefront of coating technology applications. In May 2005, the engineering of this technology was completed and applied to "Taihang" engine blades. In August 2005, the high-pressure turbine guide vanes sprayed with nano-zirconia thermal barrier coating technology solved the problem of ablation and successfully passed the long-term test of the "Taihang" engine.
10) For the first time, a monolithic casting titanium alloy intermediary case was used; its technical problems were finally solved by Beijing Institute of Aeronautical Materials.

11) The control system used at the beginning of the "Taihang" engine test was a digital ESC system, but it was not mature enough in terms of stability, reliability and anti-interference, so it was changed to a mechanical hydraulic scheme. In December 1998, the scheme Installed test run, after strict assessment and verification, can ensure the reliable operation of the engine. The original digital ESC scheme was changed to the second case, which will replace the mechanical hydraulic control scheme after the development is mature.
12) During the development of the prototype of the "Taihang" engine, new materials for powder metallurgy were used for the high-pressure turbine disks. However, as related domestic technologies have not yet fully matured, this material was replaced from the final batch.