The turbofan engine, which is a type of aircraft engine, was developed from the turbojet engine. Compared to turbojets, the main feature is that the first stage compressor has a much larger area and is used as an air propeller (fan) to push back part of the sucked air through the periphery of the jet engine.

The part through which the air in the core part of the engine passes is called the internal duct, and the outer part of the core through which only the fan air passes is called the outer duct. Turbofan engines are best suited for flight speeds of 400 to 1,000 km/h, so most aircraft engines today use turbofans as a power source.

Luo, one of the world's three major aviation power giants? Luo, Pu? Hui and General Electric have their own excellent turbofan engines, in the development of turbofan engines, Tianfeng Technology Company has just started, and it is very difficult to compete with these three companies immediately and get a share of the huge international aero engine market.

Li Tianfeng is very accurate in his positioning, starting from China, the first thing to start is the turbofan engine of the civilian regional airliner.

Although it started from China, the technical positioning of Tianfeng Technology's first turbofan engine is very high, and a large number of new technologies, new processes, new materials, and the preparation of the design outline will be used by Li Tianfeng himself.

In addition, the design of the core part of the machine, Li Tianfeng will definitely strictly control, the technical difficulty of the turbofan engine is extremely difficult, the requirements are extremely high, the key parts, the key parts, Li Tianfeng may design the sketch by himself.

If there is enough energy, Li Tianfeng is eager to design those key parts and key parts by himself, but his personal energy is often very limited, and the design of an advanced turbofan engine relies on a strong technical team. And not a single person.

What Li Tianfeng has to do is to check from the overall height, build the overall design framework, check some key parts, key parts, and even draw basic sketches or schematic diagrams. The specific design details are all handed over to Sun Xiaoping's design team.

Tianfeng Technology Co., Ltd.'s aero engine design institute has more than a dozen design offices and more than 1,000 designers, including several researcher-level senior design engineers and more senior design engineers.

Technical Center, Aero Engine Design Institute.

Over here. Li Tianfeng has his own office, in the past, Li Tianfeng came to this office relatively rarely, since some time ago, Li Tianfeng often appeared in this office, here, Li Tianfeng's main job is drawing, and there is a special drawing desk in the office.

Drawing table. Spread a snow-white drawing paper, on the table. A few pencils, sharpened to a certain thickness, the thick pencil is used to draw thick lines, and the thin pencil is of course used to draw thin lines, and in addition to the pencil, there is also a large eraser.

Popularization in computers. In the era when drawing software is very advanced, it is generally computer drawing, but in the case of drawing sketches, there is no need to mark a large number of dimensions, technical conditions, and so on. Li Tianfeng is accustomed to sketching with his bare hands, and he is very fast.

On the desktop, on the white paper, Li Tianfeng held a pencil, waved his hand, very fast, drew a few strokes, thought about it, and then painted, not long after, a sketch of a fan blade jumped on the paper, although it was drawn by hand, but it was clear and standard, reflecting a very high level.

After thinking about it, Li Tianfeng marked the main dimensions of this fan blade, and some specific dimensions, especially the blade size, all need to be strictly calculated, and Sun Xiaoping's design and technical team is enough to complete these tasks.

After drawing this leaf, Li Tianfeng stopped and thought about it, then picked up the pencil and marked the places that need attention in the design of this leaf one by one, marked these things up, looked at it, and felt very satisfied, Li Tianfeng stopped.

"Knock, knock, knock"

There were three gentle knocks on the door, and as soon as he heard this familiar voice and rhythm, Li Tianfeng knew who it was, so he smiled and said loudly: "Please come in." ”

It was Liu Wei who came in, Liu Wei held a large handful of sharpened pencils in her hand, and walked in gently, "Boss, I have prepared a lot of pencils for you, which is enough for a day." ”

These pencils, according to Li Tianfeng's requirements carefully and meticulously cut into two kinds, one thick, one fine, all are hand-sharpened, although the pencil sharpener is very convenient to use, but it is difficult to meet Li Tianfeng's requirements, generally hand-sharpened pencils.

Li Tianfeng smiled: "Put it here." ”

There are two pen holders in one corner of the table, one for the red thick pencil and one for the blue thin pencil, which is also very convenient to hold and use.

Liu Wei smiled, put these pencils into the pen holder one by one, then moved a stool to sit down, carefully sharpened Li Tianfeng with a blunt pencil one by one, and then gently put the pen holder back.

Liu Wei naturally saw the sketch that had just been drawn, and Liu Wei said: "Boss, this is an aero engine blade, look at this length, it should be a fan blade." ”

Since joining Tianfeng Technology Company, Liu Wei has often read some aviation books and magazines, and she also knows a little thing. ”

Li Tianfeng nodded, a voice sounded outside the door, Sun Xiaoping walked in happily, and said loudly: "Mr. Liu, you are really good-looking, you can see at a glance, yes, this is the fan blade of our new engine." ”

Sun Xiaoping came over, just looking for Li Tianfeng, some design and technical things, whenever he was not sure, Sun Xiaoping would come over and humbly ask for advice.

Previously, Sun Xiaoping presided over the design and completion of the turbofan B engine, and in the past, Sun Xiaoping was also the chief model engineer of the turbofan B engine, and at present, the turbofan B is in mass production in the E factory, producing 50 or 60 units per year, mainly equipped with a new type of advanced training aircraft in China.

Now, Sun Xiaoping has been appointed as the chief designer of this engine, which is like a fish in water, but this turbofan engine has a very high technical content, and Sun Xiaoping is not sure about many new design technologies.

This problem is also a problem with the design of the fan blades, but I didn't expect that as soon as I entered the door, I saw this sketch of the fan blades, Sun Xiaoping's eyes lit up, and he immediately said loudly and happily.

Liu Wei smiled slightly: "Mr. Sun, I came over to discuss design issues with the boss again." ”

Sun Xiaoping said: "It's not a discussion, I'm here to ask for advice." ”

Seeing this, Li Tianfeng smiled slightly, "Mr. Sun, what's the matter?" ”

Sun Xiaoping said: "Boss, we are designing the fan part, and there are some problems that are not accurate, and we need your guidance." ”

Seeing the design sketch of the fan blades on the desktop, Sun Xiaoping's eyes lit up again, and he said in surprise: "Boss, you have drawn all the sketches." ”

Li Tianfeng nodded and said: "This turbofan engine, although it can only be regarded as a small and medium-sized turbofan engine, but the technical content is high, the requirements are also extremely high, the design of the core part of the machine will be very difficult, the main parts of this part, I will personally complete the design sketch, you follow my design sketch to carry out the design." ”

Hearing this, Sun Xiaoping was overjoyed, and carefully looked at the design sketch of the fan blades on the table, and said happily: "Boss, your drawing skills are extremely high, the hand-drawn sketch can achieve such a Cheng dù, and it is the first person in the entire Tianfeng Technology Company, I don't think there is a second person who can achieve such a Cheng dù." ”

Li Tianfeng scolded with a smile: "Don't shoot Lao Tzu's sycophants." ”

Sun Xiaoping smiled and scratched his head, where is the appearance of the chief designer, Liu Wei next to him saw this, sneered, very beautiful, Sun Xiaoping looked stunned, seeing this, Liu Wei covered her mouth and chuckled again.

Sun Xiaoping and Qiu Wen'an have completely different personalities, Sun Xiaoping is extroverted, Qiu Wenan is introverted and doesn't like words, however, although the two have completely different personalities, in Li Tianfeng's view, they are both loyal to themselves, and the design level is first-class in China.

Li Tianfeng finished scolding with a smile, his face was straight, and he said to Sun Xiaoping: "Mr. Sun, let me tell you about the design of this fan blade, this is a wide-chord fan blade, using the latest and most scientific fan blade design in the world.........

When it comes to the design of fan blades, it has gone through several generations internationally. The external thrust of the turbofan engine comes completely from the thrust generated by the fan, and the quality of the fan directly affects the performance of the engine, which is particularly obvious in the turbofan engine with high channel ratio, and the turbofan engine of Tianfeng Technology Company is a high channel ratio engine.

The fan development of turbofan engines also went through several processes. At the beginning of the turbofan engine, due to the limitation of the power of the internal core engine and the mechanical strength of the fan material, the channel ratio of the turbofan engine is impossible, for example, in the three originators of the turbofan engine, the CJ805-23, which has the largest channel ratio, is only 1.5, and the fan used in the CJ805-23 is still a unique rear fan.

At this time, most of the turbofan blades use slender fan blades, and when the fan blades become slender, their bending and torsional stress increases, and the problem of vibration in the work also emerges. In order to solve the problem caused by the slender fan blades, Pratt & Whitney adopted the method of damping bosses to reduce the vibration caused by the fan blades.

Fan blades with damped bosses are considered to be the second generation of fan blades.

Just now, the fan blade designed by Li Tianfeng is naturally not a fan blade with a damping boss, but another kind of fan blade that is much more advanced than this.

…………

There are a lot of things today.,Only two more.,I'm very sorry.,The first one is sent.。 (To be continued......)