Chapter 417 officially begins!
In fact, as early as 1904, the German mechanic Ludwig Prandtl (not the Planck who studied quantum mechanics, although both men were German and lived roughly in the same era) In experiments on the boundary layer of flow around a cylinder, it was found that air flow separation can be delayed by actively pumping the adsorption surface layer.
But until now, no one has seriously considered applying this principle to the field of compressor design.
Some cutting-edge laboratories, including MIT, have only proposed related possibilities, and have successively begun to conduct some research on mechanisms and feasibility.
So we can’t blame Liu Yongquan and others for not thinking about this before.
After all, Chang Haonan introduced this ultra-high-load adsorption-type curved-sweep combined leading edge edge blade with a "calculation example" before, and did not mention the specific application scenarios and basic principles of this thing.
And to be honest, for most of the audience sitting below, it was not easy to just understand the numerical calculation method in the blade design process.
Those who can produce as little as half a notebook like Liu Yongquan are already among the best.
It’s normal to not have time to think too much.
“Boundary layer suction can remove the high-entropy and low-energy fluid in the compressor. The lower the entropy value of the initial fluid before compression, the same pressure will be increased for the same mass of fluid in a multi-stage compressor. The less work is consumed and the compression efficiency increases..."
"This is the formula of Karman's momentum equation. We don't even need the assistance of a computer. By deriving it from a theoretical level, we can find that when the boundary layer is well adhered to the suction, the decrease in the momentum thickness at a certain position downstream and the suction The amount of decrease at the position is the same; while when the boundary layer is near separation, the decrease in momentum thickness at a certain position downstream is magnified by an exponential factor compared with the decrease at the suction position..."< br>
The basic principles of boundary layer suction did not break through the content of ordinary undergraduate physics. Even if it involves engineering applications, everyone quickly understood what needs to be done next under Chang Haonan’s explanation. :
“So we must find the specific location where flow separation occurs in the boundary layer, so that we can...improve the efficiency of the single-stage compressor as much as possible?”
“That’s right.”
Chang Haonan nodded happily:
"This technology currently has two application directions. First, as I just said, high tangential speed adsorption compressors can be used in military small bypass ratio turbofan engines, using one-stage adsorption fans to replace the original multi-stage fans. This reduces the weight of the fan and achieves a higher thrust-to-weight ratio. "
"The second is the low tangential speed adsorption compressor, which can be applied to turbofan engines with large bypass ratios and achieve the same pressure ratio. The reduction of blade tip tangential speed and rotational speed will improve the vibration characteristics and acoustic performance of the engine. Of course, this should be a future thing for us..."
"So before carrying out the overall design, we must first Solve these technical problems..."
Hayide next to him has opened a notebook and started taking notes.
Although he is not the technical person in charge of the Taihang project, as the chief engineer, he certainly cannot understand the entire research and development process.
What's more, Haiyide himself also has a technical background. Even if he has left the forefront for a few years, his most basic sensitivity is still there -
With Chang Haonan's current progress speed of a rocket, the other party is completing After the Turbofan 10 project, we will at least invest in the research and development of the next generation aeroengine, and may even go directly to more basic and larger-scale projects, instead of wasting time on personally designing the third-generation core engine. Derived from other aviation engines of the same generation.
Provide at most some technical guidance.
The other party has just made it clear that the technology acquired during the development of the turbofan 10 also has application value in a wider range.
Hai Yide still has a relatively clear understanding of himself. He knows that his ability to make some achievements in the field of aviation power in this life is already his limit, so after the Turbofan 10 project is completed, This is the time for these people who have participated in Turbofan 10 to show their talents.
As for now...
Listen well and study hard.
“This is just one of the key technical issues.”
Chang Haonan put down the pen in his hand and said:
“Our foundation in aero-engine development is indeed It is too thin, and there is no ready-made experience and data to follow for many things, so we have to start from scratch. For example, the new active cooling technology I just mentioned requires a design team responsible for the turbine part to be responsible for research, as well as the casing part... Fortunately, there are relatively few problems with the combustion chamber and afterburner, and many of the technologies applied to the turbojet 14 can be directly used.”
"This is just the design level. The 410 factory is responsible for the production and manufacturing at the same time. Especially the hot-end components, single crystal turbine blades, and the main bearings of the entire engine. The working conditions are very harsh, and the manufacturing level determines How many cycles can our engine be used? Although the life requirements can be relaxed on the premise of improving performance, the reliability cannot be too low. After all, there are single-engine aircraft to use. This needs to be coordinated by Mr. Hai. I may We will provide some help when necessary, but the main focus must still be on basic research..."...
Although it is only a small meeting of less than ten people, it is still enough. It lasted an entire afternoon.
In fact, Chang Haonan is equivalent to dismantling and distributing the work involved in the entire project.
“The entire project team is expected to be initially divided into nine technical directions: overall structural design, compressor, combustion chamber, turbine, fan, casing, other auxiliary components, cold processing technology and hot processing technology to carry out work simultaneously. , each direction will be divided into different groups according to specific topics. As for the selection of key members for each direction..."
Chang Haonan stopped the pen in his hand and looked at Hai Yide next to him:
"Mr. Hai?"
The other party is the chief engineer responsible for administrative leadership after all. In terms of personnel allocation, he It's not good to directly overstep your authority.
At least be polite.
What's more, Chang Haonan himself is not an employee of the 606 Institute. His previous contact with this place was limited to the Turbojet 14 project. Therefore, in terms of understanding of the situation, he is definitely not comparable to the native Haiyide.
The latter nodded immediately:
"I will assign the key personnel in each direction according to their previous work experience, especially the experience in participating in the Kunlun project. As for the person in charge of each topic..."
After Haiyide said this, he lowered his head and thought for a moment.
The impact of this aspect is so great that even he cannot come up with a list immediately on the spot, not to mention that it also involves colleagues from other factories.
Although Institute 606 is responsible for the overall design, we are all brothers in the unit after all. If you really don't save any face, it will not be good.
"As for the person in charge, I will first understand the specific situation in the next few days and make a list of people with more relevant experience. Why don't we decide the specific candidates at that time?"
Hai Yide has not done so before. He's not being polite, he has a clear understanding of his position.
Considering the actual situation of the Taihang project, no matter who becomes the chief engineer, he will mainly be responsible for providing administrative support.
And take the blame.
So he still handed over the decision-making power of key positions to Chang Haonan.
"That's fine. The complete task allocation plan will be finalized at the all-member meeting next week."
Chang Haonan closed the notebook in front of him and handed it back to Liu Yongquan:
"But before that , we still need to seize the time to start the research work in several key directions. In addition, I will personally be responsible for the turbine and thermal processing technology. As for the compressor, I think it can be left to Comrade Liu Yongquan. What do you think? "
The latter, whose name was suddenly called, didn't even react immediately.
Until Haiyide called his name again:
"Yongquan, show your attitude?"
"Promise to complete the task!"
(End of this chapter)