Breakthroughs in key technologies are made, and the rest falls into place.

The D-50 turbo gas power unit is ready-made, and with the technological breakthroughs made by Tengfei Group in aero engines over the years, the WD-52ML turbofan engine came into being.

The whole engine is a twin-rotor turbofan structure, with a diameter of 1260mm, a length of 2861mm, and a net weight of 872 kg.

The fan is a 1-stage axial flow type, the blades and discs are made of titanium alloy, of which the number of blades is 28, using the forged wide chord, boss-free solid structure blades accumulated by Tengfei Group for many years, the maximum speed is 7360 cycles \ minutes, and the unique connection mechanism is adopted, which makes the fan replacement very convenient, and the fan blades that need to be replaced can be directly processed without disassembling the engine.

The compressor adopts a 10-stage high-pressure compressor structure, of which the first three stages apply the mature overall blisk structure of Tengfei Group, and the blades are made of titanium alloy and the unique linear friction welding of Tengfei Group is used to fix the blades on the blisk of the high-pressure compressor, so as to achieve the technical indicators of the overall blisk.

The rest of the 7-level blades are made of nickel alloy steel, using the traditional detachable structure, and the blades can be replaced separately, so the configuration is because the twin-rotor engine structure is conducive to improving efficiency, and the second is to reduce production costs.

For this reason, the combustion chamber is made of nickel alloy steel segments, which are made by complex machining, which alone cannot meet the ultra-high temperature in the combustion chamber, so Tengfei Group has added a layer of high-temperature resistant ceramic coating to its interior, so that the fuel can be fully combusted, so as to reduce pollution, increase fuel efficiency, and improve economy.

However, to achieve this purpose, the flame barrel is required, and the flame cylinder of the WD-52ML turbofan engine adopts a central low-pressure fuel injection system, with 18 flame nozzles, which can easily ignite the fuel and fully burn it.

In addition, the flame barrel is particularly maintainable, can be easily disassembled, and can also be inspected using Ascendas Group's borehole detection equipment.

Of course, the fan, air compressor and combustion chamber are strong, and if the turbine is well coordinated, it is useless, and the turbine of the WD-52ML turbofan engine adopts a high and low turbine structure.

The high-pressure turbine is 2-stage and the low-pressure turbine is 4-stage.

The six turbine turbine discs are all made of powder superalloy technology, of which the high-pressure turbine blades are made of nickel alloy single crystal casting cold hollow blades based on powder superalloy technology, and the air film cooling technology and high-temperature resistant ceramic coating technology are adopted.

The combination of these advanced technologies has increased the pre-turbine temperature to 1360 degrees Celsius, resulting in a qualitative leap in the performance of the WD-52ML turbofan engine.

In the low-pressure turbine, the first two stages of the low-pressure turbine use powder superalloy technology for nickel alloy single crystal blades, which are coated with high-temperature ceramics but not cooled by air film, while the last two stages use ordinary nickel-based alloys.

While reducing costs, it also ensures the reliability of the engine.

After such integration, the maximum thrust of the WD-52ML turbofan engine reaches 5.2 tons, and the thrust-to-weight ratio is close to 6, which is 5.96.

It is no exaggeration to say that it is the culmination of Tengfei Group's more than ten years of aero engines.

Its great significance is not only to demonstrate the super aero engine technology research and development capabilities of Tengfei Group, but more importantly, the WD-52ML turbofan engine will become the foundation of Tengfei Group's aero engine field in the next ten years.

Because the core engine derived from the compressor, combustion chamber and high-pressure turbine in the WD-52ML turbofan engine fully meets the initial requirements of the second generation core engine of the Tengfei Group, and with a little improvement and perfection, it can become the main core engine of many aero engine models of the Tengfei Group in the future.

Even if we don't talk about the important role of the core engine in the future, as far as the WD-52ML turbofan engine itself is concerned, the importance of the Ascendas Group is also self-evident.

Because with the success of the WD-52ML turbofan engine, Tengfei Group's Haidongqing plan can continue to advance, when the 50-seat and 70-seat regional airliners can not only land smoothly, not to mention, the ultra-luxury long-range business jets can also be launched without hindrance.

In addition to regional airliners, the impact on Ascendas Group's trainer aircraft is also huge.

You must know that the WD-52ML turbofan engine can be easily changed to a small bypass ratio turbofan engine, Tengfei Group has done tests in this regard, the small bypass ratio version of the WD-52ML turbofan engine, the normal thrust will drop to 4.8 tons, but a section of afterburner is added, and the thrust of the engine will reach 7.6 tons when the afterburner is turned on.

This indicator has surpassed the turbojet-13 engine currently used by the Jianjiao 7MAX.

A turbofan engine that is better than turbojet-13, this is not only to solve the problem of Tengfei Group's Jianjiao 7MAX, it is a very subversive existence for the whole country, you must know that there are many aircraft equipped with turbojet-13 and the previous generation turbojet-7 engine, J-7 needless to say, the current main force of domestic air combat J-8 II is used in turbojet-13 engine.

In the early years, it was like replacing the turbojet-14 with greater thrust, but the reliability of the engine was not high, and it was easy to fly into the sky with inexplicable spray parts, so I had no choice but to change back to the turbojet-13.

Now a version of the WD-52ML turbofan engine with a small bypass ratio that is better than the turbojet-13 is available, and its breadth of progress is self-evident.

The reason why it was not immediately launched to replace the turbojet-13 and occupy the aero engine market of domestic military aircraft is mainly because of the size, after all, the diameter of the large bypass ratio of the WD-52ML turbofan engine is only about 1.2 meters, and the diameter of the small bypass ratio is less than 0.8 meters.

And the engine compartments of J-7 and J-8 have long been given to death by turbojet 7 or turbojet 13 with a diameter of about one meter.

It is obviously unrealistic to let the J-7 and J-8 adapt to the WD-52ML turbofan engine, which is equivalent to rebuilding the two aircraft, and can only be the WD-52ML turbofan engine to adapt to the domestic active combat aircraft.

Therefore, the size must be increased, and the various indicators of the aero engine can be involved in the whole body, increasing the size seems simple, but in the aero engine it means an increase in air intake, an increase in the compression ratio, a more violent combustion, and a further increase in the temperature before the turbine.

The result is a further increase in performance.

To this end, Tengfei Group has calculated, without making other adjustments, based on the core components of the WD-52ML turbofan engine, a small bypass ratio turbofan aero engine with a diameter of 1050mm, a length of 5684mm and a net weight of 1.2 tons, the normal thrust will be increased to 5.6 tons, the afterburner thrust will reach 8.7 tons, and the thrust weight will reach 7.

This value has been able to compete with the Soviet RD-33 turbofan engine and the American F-404 engine, only worse than the F-414 engine that the United States is about to complete the development, the problem is that GM can develop F-414 on the basis of F-404, why can't Tengfei Group continue to move forward on the basis of WD-52ML turbofan engine?