On Li Tianfeng's desk is a main bearing of the turboshaft D engine. This is a bearing produced by Linhai Technology Company according to the improved process. Li Tianfeng looked at this bearing with great enthusiasm and prepared a magnifying glass.

"It's so exquisitely made and the appearance is so beautiful." Li Tianfeng looked at it with a magnifying glass, and felt a burst of praise in his heart.

Linhai Technology Company has produced several major bearings of the turboshaft D engine according to the improved new process, but each batch is not large in quantity. If the engine is to be installed, it will only be used for two or three engines.

These bearings have been tested by Linhai Technology Company and have also conducted preliminary tests on bearing test equipment, and the quality has been improved a lot. So, these bearings have been sent to Tianfeng Technology Company and will be equipped with a turboshaft D engine for verification and testing.

Li Tianfeng took the bearing and looked at it very satisfied. According to Li Tianfeng's professional perspective, the bearing has excellent quality, which is comparable to imported aviation bearings from abroad.

In addition, Li Tianfeng also looked at the test report and test report of this bearing, and the data were very good.

Li Tianfeng looked at this bearing with satisfaction, as if he couldn't put it down. With high-quality aviation bearings, not only will the reliability of the turboshaft d and turboshaft e engines be further improved, but the turbofan engine under development will also have high-quality aviation bearings for use.

However, how can the bearings of aircraft engines, especially the main bearings, be a joke? Even though Li Tianfeng personally believes that the bearings are of good quality, they have also undergone strict verification and test drives and installed on the aircraft engine. After strict verification and test drives, they can only be installed on the aircraft engine in batches after strict inspections and conclusions.

Although he will have to test the car in the end, Li Tianfeng was already very satisfied. If the test car was successfully passed and these bearings could fully meet their requirements, that would be of great significance. It would not only be that his aircraft engine had high-quality bearings. Instead, it filled the domestic gap and broke the world's bearing giant's monopoly on high-end bearings.

Thinking about it is enough to make people excited!

At present, high-end bearings have become a shortcoming in my country's aviation engine research and development. Bearings have a high technical content and can be used as an important criterion for measuring a country's scientific and technological and industrial strength. In today's world science and technology, industrial powers are without exception.

The reason why my country is a big industrial country rather than an industrial power. An important manifestation is that the bearing industry is large but not strong. The main production is mid- and low-end bearings, while high-end bearings mainly rely on imports.

High reliability and high-precision top-level bearings used for aircraft engine matching have become the "Mount Everest" that is difficult to cross in my country in the research and development of aircraft engines.

Taking the main bearing of the aircraft engine as an example, the main bearing is one of the key components of the aircraft engine. Operating under high speed, high temperature and complex stress conditions, the quality and performance of the main bearing directly affect the engine performance, life and reliability.

One of the key indicators of an aircraft engine is high reliability. To ensure reliability, one of the prerequisites is to ensure that the bearings in the engine have the life of a long-life main bearing. The military aircraft aircraft engine requires more than 3,000 hours, and the civil aircraft aircraft engine requirements are higher, reaching tens of thousands of hours.

The bearing working environment in aircraft engines can be described as "purgatory". They not only have to operate at a long-term high speed of tens of thousands of revolutions per minute, but also have to withstand various forms of stress extrusion, friction and ultra-high temperatures.

In addition, for general structural components, even if there are mild cracks, it can be used safely. This is professionally called damage tolerance. Key transmission components such as aircraft engine main bearings do not have damage tolerance, and they will never allow damage such as cracks during use. The main bearings of aircraft engines in my country are currently limited in life, and bearings have become the "short board" in the wooden barrel principle.

At present, the research, development, manufacturing and sales of high-end bearings are basically monopolized by the world's four major bearing giants, namely Timken, Japan's NKK, Sweden's Sk, and Germany's Schaeffler (ag).

Now, in this monopoly situation, the shortcomings in domestic aviation engine research and development are about to be broken by himself. Li Tianfeng just thought about it this way and felt a little excited. This is completely historical significance.

In addition, Li Tianfeng, Linhai Technology Company, owns 40% of the shares, which is also half of his own company. With such a bearing manufacturing process, high-quality medium and high-end bearings will be continuously produced, with great development prospects.

Perhaps, in less than two or three years, this company will develop into a domestic bearing industry giant, and it is possible to monopolize the domestic mid- and high-end bearing markets. In time, it will develop into a world bearing industry giant, which is comparable to the current four major bearing industry giants in the world. This is entirely possible.

Li Tianfeng seemed to be looking at this bearing without getting tired of it. After watching it for a long time, Li Tianfeng picked up the phone and arranged the test drive for the bearing verification test drive. First, the major bearings of the turboshaft D engine were verified and tested. Then, the test drive for the turboshaft e engine will be carried out.

The test run test was arranged properly, and Li Tianfeng thought to himself, don’t let yourself down, you must meet your requirements. If the test run is really completed successfully and fully meet your own quality and performance requirements, it would be so cool.

………

As the days pass by day, it will take several months for this turbofan engine from Tianfeng Technology to enter the comprehensive detailed design stage.

The fan part was the first to complete the design, and the trial production of the fan blades was even almost completed. The design of the high-load compressor was completed. After the preliminary design was completed last time, a technical review meeting was conducted, which collected many various problems. The design team led by Sun Xiaoping has completed the design improvement and improvement again, and has conducted the technical review several days ago.

The design of the high-load compressor is very technical, and it has adopted so many new designs and new materials. The second design review has basically been passed. There are a few problems that need to be improved and improved. Finally, it may be a third review.

Li Tianfeng estimated that after completing the third design review, the design of the compressor part can also be basically finalized, waiting for various verifications and tests in the future.

Today, in a conference room of the Aero Engine Design Institute, the combustion chamber part underwent a second design review. The combustion chamber has also completed the first design review and has also been designed to improve and improve based on the last review. Now the second design review is underway.

Turbofan engines, several important components, fans, compressors, combustion chambers, turbines, tail sprays and accessories, technically, the overall technical content of turbofan engines is higher and more complex than that of turbine shaft engines.

Let’s first understand that modern advanced turbofan engines, modern fighter jets, military transport aircraft, civil aviation trunk passenger aircraft, etc. all use turbofan engines.

Simply put, a turbofan engine has two concentric ducts, consisting of five parts, including fan, compressor, combustion chamber, turbine, nozzle, etc. The compressor, combustion chamber and turbine are often collectively called the core engine of the engine.

The difference between turbofan engines for fighters and transport aircraft and civil aviation passenger aircraft is mainly in the fans. The engines of passenger aircraft generally use large-diameter fans to reduce fuel consumption; the diameter of the engine fans of fighters is generally small for supersonic flight.

Air flows in from the inlet port of the turbofan engine, compresses by the compressor, and mixes and burns with kerosene in the combustion chamber. The high-temperature and high-pressure gas expands through the turbine and nozzle, and finally sprays out from the tail nozzle at a high speed. Part of the thrust of the turbofan engine comes from the reaction force generated by the injected gas; the other part is the turbine-driven fan, which rotates and drives the air and sprays out through the outer duct of the engine.

Why is turbofan engine so difficult?

Imagine that the maximum afterburner thrust of the Al-31 turbofan engine of the Su27 is 125 tons, and two Al-31s can push the Su27, which is more than 20 tons, to fly at more than twice the speed of sound. However, the fan diameter of the Al-31 is less than 900 mm and the turbine diameter is less than 300 mm.

Basic physics principles: forces interact, that is to say, a fan of such a small size, the turbine will always bear 125 tons of force. To put it more vividly, everyone should have seen the performance of a strong man pushing a car with a steel gun on his throat. The turbofan engine is probably the same. It is just that the strong man pushes the car and moves slowly, while the turbofan engine needs to push the aircraft to fly at twice the speed of sound, and each component must withstand the test of extremely harsh high temperature and high pressure.

In addition, a turbofan engine used for supersonic fighters is generally only about 1 meter in diameter and about 4 meters in length. Taking Al-31 as an example, such a small cylindrical object is to be stuffed into a 4th-level fan, a 9th-level compressor, and a 2nd-level turbine, which can converge-expanding nozzle, a combustion chamber, and afterburner. Cooling air channels must be arranged between them, and fuel control systems must be installed around them.

Therefore, designing and manufacturing a high-performance turbofan engine can be said to be extremely difficult to "make a dojo in a snail shell". In the world, only three companies, Rolls, Rolls, Pratt, and General Motors, are from the United Kingdom, Pratt, and General Motors. Both Russia and France are second-rate. This is a real high-tech industry and a real monopoly industry.

This turbofan engine from Tianfeng Technology is to break this monopoly barrier and let several major aviation giants know that China can also develop and manufacture the world's advanced turbofan engines.

………

Two updates today, the first update will be given.

Sorry, I can only update two chapters today. There are too many things to do today. I have meetings in the morning and afternoon, so I don’t have much time to write. I originally planned to completely lose my last update. (To be continued.)
Chapter completed!