After figuring out the joints in this, Yang Hui was really embarrassed, and he didn't know whether to say that the Red Flag Factory was too stingy, or whether to say that the blood feud between the two sides was too misleading.

All this is because of the engine dismounting, if the turbofan 9 continues, naturally there will be no cooperation between the Hongqi factory and the dawn factory, if the turbofan 6 is successful, there will also be no turbojet 14 on the horse, these are all to make people.

Yang Hui can't comment on the practices of the Hongqi Factory, but now the Hongqi Factory has come up with their technology, that is, the guests of the base are the partners.

"If this is the case, our project is even more promising, our new aircraft is waiting for the engine to be cooked, and it can't help but be in a hurry."

After seeing the most critical high-temperature turbine blades, the whole person was refreshed. As Director Bai continued to go to the office on the side, he saw that when Yang Hui first came to the institute, he lacked R&D funds and wanted to sell tea eggs by himself, but now Brother Dabo's annular combustion chamber project 'Ding Xingwang', and Yang Hui was embarrassed to bother.

Finally, I went to the fan R&D group, here the turbofan is another key part of the engine, where it is necessary to design a fan with strong compression efficiency, the stronger the fan compression efficiency, the higher the efficiency of the natural engine.

Just standing outside, I can't bear to disturb the research and development inside, Director Bai briefly introduced.

"We designed the second and third stages of the engine fan ourselves, and the first stage fan is more difficult, so we worked with the Hongqi factory. Since we are a medium-thrust engine with strict size constraints, the first stage fan should have a high compression efficiency, and we also chose to optimize the fan blade shape to improve efficiency. ”

Optimizing the blade shape is a good way to increase efficiency without increasing the size, but without the revolutionary blade shape, there will be no too amazing breakthrough, but fortunately, this is only a small bypass ratio turbofan, and the fan size is not enlarged too much.

Afterburner, new outer engine casing, engine control system. You don't need to pay much attention to these aspects, as long as the money is invested, you can still do it with the current technical capabilities of the institute.

I went all the way to the new engine development data room, and finally figured out the progress of each engine project. At this time, Director Bai suddenly said mysteriously to Yang Hui.

"Yang Hui. You come with me and show you something, this is one of the biggest headaches right now, and I can't figure out what to do about it. ”

The mysterious Director Bai successfully hooked Yang Hui's curiosity, and the things that could give the director a headache should be quite big. Let's take a good look.

Open the reference room and go inside, until you reach the innermost part of the reference room, where there are several thick piles of books, which seem to be in the original English version, which is a little intriguing. Shouldn't this kind of thing be put in the library? How did I run to the data room?

Walking over and picking up a thick book and looking at it carefully, Yang Hui realized what it was. After seeing it, Yang Hui knew that this thing was definitely a hot potato.

"Director, this is from the Hongqi Factory? The British technical specifications for engine development can be no fun at all. What's going on? ”

Knowing that Yang Hui understood the meaning of this book, Director Bai didn't say much, and went straight to the point: "That's right, this is the engine development specification of the British Rolls-Royce company, which was handed over to me by Chief Engineer Yu, and asked us not to follow the old domestic specifications in the development of new engines." Our technical specifications were taken over by the USSR and now cannot be adapted to the new requirements. ”

Hearing what Director Bai said, Yang Hui deeply felt that according to the old technical specifications, there was no way to guide the development of a new generation of engines. The development specification of the first generation of engines corresponds to the development ideas of the first generation.

The old norms in China are backward, and these specifications provided by Rolls-Royce are not much advanced, which was developed in the sixties. At that time, the idea of developing aircraft was still somewhat backward compared with the current mainstream thinking.

In the 60s, after many major accidents in the 50s, people not only found out the aerodynamic reasons, but also found many deficiencies in the design and structure of the aircraft.

Before the 60s, the design idea of the aircraft was still the old-fashioned dynamic strength design idea, which is to put it bluntly, that is, to calculate and design the structure according to the material properties of the aircraft. It is believed that as long as the structure can withstand the weight and maximum load of the aircraft.

But these do not take into account the working environment of the aircraft. During the flight, various external forces are repeatedly cross-applied to the aircraft, and many times of deformation will occur, resulting in fatigue. Like what:

When the aircraft does not take off on the ground, the wings are subjected to their own gravity and the gravitational load of the objects mounted under the wings, and the wings will deform downward, but after takeoff, there is lift, and the wings are upturned again. Under such repetition, the wing continues to repeat the deformation, coupled with other special large overload maneuvers, at this time, the manufacturing material will be fatigue damage, with fatigue damage to a certain extent, the structure will be destroyed, and the destruction of the aircraft is inevitable.

This is fatigue damage, which was only discovered in the sixties, and after the discovery of fatigue damage, various machinery industries have benefited more or less, and the idea of fatigue damage has also been introduced in engine manufacturing.

To sum up, it is the fatigue safety life design idea: and this is the idea of Spey engine development, which is expressed through the design specifications and specifically guides the engine design test.

The design concept of fatigue safety longevity noodles has been developed since the 60s and has not been replaced in later generations. However, the fatigue safety life design idea refers to the fact that there can be no defects in the structure when designing, and if there is a defect, it will be scrapped.

This idea permeated Spey's design, as did the Soviet design code introduced by the Republic: as soon as there was a defect or crack in the structure, it would be scrapped.

The products under the guidance of the fatigue safety life idea are naturally quite reliable, but also quite wasteful, and some parts cannot be used if they are not cracked. In many cases, there is a long service life between the crack and the complete fracture of the part, and it would be too wasteful to scrap it like this.

What to do at this time? So in this case there is a new design idea: damage tolerance and durability (economic life) design thinking.

The idea is quite interesting and economical, and the products produced in this design idea are no longer scrapped as soon as they crack, but continue to be used.

There are cracks are not terrible, just continue to use, according to the damage tolerance and durability design idea of the design of the engine, in the design test has been tested out of the data of parts fracture, know when the parts will break after the damage, then continue to use, usually pay attention to more checks, return to the factory for overhaul on time.

The products designed by such a design idea are naturally long-lasting, which will squeeze out all the service life of the parts and truly make the best use of them. That's why the engine life tested by this design idea is called economic life.

Having said so much, I finally reacted. Such an economical design idea, it must be the favorite of the poor, and the flying machine designed by such an idea must be the favorite of the republican ** team now, and now the domestic army is the most humble time, and I can't wait to spend a penny as a penny.

It is simply undesirable to be able to save money for the military while ensuring the quality of products.

The design idea is indeed very good, but in the 83 years, the damage tolerance design is still in the exploration stage, and there is no country that has really introduced this idea into the design of the new machine, so naturally the old-fashioned fatigue safety life idea is used in the design specification, which is already backward in Yang Hui's view, and it is not in line with the national conditions of the republic.

In the last life, this design idea was introduced in the design of military aircraft in the United States in the mid-to-late eighties, and in the early nineties in the Republic. Now eighty-three years is the eve of dawn, and it is undoubtedly the best to be the first to introduce this idea, and the early bird will eat the worm. (To be continued.) )