The imperial capital sent people to the base, this is sooner or later, Director Bai presided over the revision of the old military standard specification has been several months, Yang Hui has been familiar with the size of the things in the institute for a few months, and the revision of the same specification has also begun to get on the right track, Director Bai has probably figured out a set of revision methods, and the development of engine parts under the guidance of the new specification has achieved initial results.

"Yang Hui, this time the imperial capital sent someone to investigate our non-compliance with the provisions of the military standard design, I think you also know, it is said that this time there are people from the aviation industry standard revision office above, as well as Wu Laodu, it looks like a bit of a mountain rain is coming, if I have a problem this time, you must continue to carry the banner, you must develop this engine."

Director Bai's pessimistic mood permeated the office, Yang Hui did not participate in the revision of the new norms under Director Bai's repeated orders, and now there is no good way for Yang Hui to deal with the new norms, but Yang Hui has a way to deal with the above investigation team at this time.

"Director, the core engine of our new engine seems to be developing quite well, and I don't know when we can start testing, which is very important to us now."

When it comes to the development of the core engine, Director Bai has no reason not to be excited, now the development of the core engine of the new engine is quite good, the compressor has not been changed, but the combustion chamber and high-temperature turbine have undergone major surgery, but the progress is very good.

When it comes to the development of the core engine, Director Bai also forgot about the unpleasantness for the time being, and introduced the latest situation: "Now we have introduced the concept of the core engine in the development of the new engine, although all the subsystems of the entire engine are developed together in parallel, but our core engine development is developed according to a whole. ”

The core engine is the high-pressure compressor, the combustion chamber, the high-temperature turbine and a spindle connecting the high-pressure compressor and the high-pressure turbine, these three components are the most critical parts of the aero engine, and they are also the most problem-prone parts. In order to solve the problem of these three key parts, there is a concept of core machine design according to a large system integration.

Continuing to introduce the development process of several major parts of the core machine: "Our high-pressure compressor has not been changed, and when we got the information of the high-pressure compressor, we did the test, and according to the damage tolerance design theory, we found a great surprise in the test. ”

The more he talked, the more excited he became, Director Bai stood up and found the test data of the high-pressure compressor in the pile of documents. confidently pushed it in front of Yang Hui.

"Look, this is the test data for our high-pressure compressor, it was the first component to be tested, and the test data is very encouraging."

Pick up the materials and look at them carefully. The data is indeed as Director Bai said, Yang Hui was very excited when he saw it, and his hands holding the information were trembling, which was really unexpected.

"The first fatigue crack appeared in 1,100 hours, after a long period of testing. Compressor blade breakage appeared in 1,700 hours, and in 1,800 hours began extensive damage. This is all a good thing, if the life of the compressor can be so long, we don't have to worry about the compressor, we can conservatively calculate, it can also reach 1,400 hours. ”

This is the case with damage tolerance design, usually the parts have cracks, and there will be a long period of life until the final scrap, but there is a margin in the design.

Take this high-pressure compressor, for example, the first break occurred in 1,700 hours. Be conservative and set the economic life to 1,400 hours, of which 300 hours is the margin, and with a margin of 300 hours, the risk can be guaranteed to be minimized.

Listening to Yang Hui's heartfelt words under excitement, Director Bai also said with certainty: "Yes, according to the design of this damage tolerance idea, the life of our high-pressure compressor can be extended to 1,400 hours. ”

After talking about the data of the compressor, Director Bai took out another document bag, and the document tape was stamped with the seal of the Hongqi Factory, I don't know what it is. But it is certain that these are related to the Hongqi factory.

The bulging document bag is also filled with information, and these are the data submitted by the Hongqi Factory.

"Look, this is the data of the new engine high-pressure rotor spindle that we commissioned the Hongqi factory to do, and they followed our requirements. The test was carried out with the design idea of damage tolerance, and it was also very good on the spindle, which was a pleasant surprise. ”

Yang Hui didn't listen to Director Bai's sales, and directly took the documents in Director Bai's hand to see that Hongqi Factory has a very good set of research on engine life.

Not to mention the turbofan nine developed by Hongqi Factory in later generations, this engine was originally known for its longevity. The technology is all from the United Kingdom, which does not reflect the real strength of the Hongqi factory. The real strength of the Hongqi plant is manifested in their main product, the turbojet eight, which is the engine that powers the Republic's H-6 bomber.

After the turbojet 8 engine was delivered to the troops in 67 years, in the course of many years of improvement, it had reached 800 hours of first turn life, which is not ordinary, and the total life of the prototype AM3 engine of the turbojet 8 engine in the Soviet Union was only 800 hours.

The same is 800 hours, turbojet eight in 800 hours of use can not worry too much, only need to pay attention to daily maintenance, 800 hours after a major overhaul, you can continue to use, life easily break through 1,000 hours is not too simple; The prototype AM3 was scrapped after 800 hours.

This all reflects the attainments of Hongqi Factory in the life of the engine, and now the new engine spindle is handed over to Hongqi Factory to do, which is naturally different.

The data on board reads: "The main shaft of these high-pressure compressors cracked for the first time in 1,400 hours, and broke in 1,600 hours. That's pretty good, we can get the spindle life just stuck in this 1,400 hours, and there should be no problem. ”

Although the engine spindle is very demanding, and cracks cannot occur in use, this is not absolute, and it is no problem to be stuck in the crack period in the damage tolerance design idea.

1,400 hours just stuck on the crack, Director Bai is more conservative about this, the spindle is the most careless, Director Bai set the total life of the spindle at 1,350 hours.

"That's right, the engine spindle does not have the concept of the first turn, as long as the spindle cracks will be scrapped, I thought about it, or decided not to use the damage tolerance design in this most important load-bearing component, according to the fatigue life to design, 1,350 hours is the maximum use of the upper limit, 50 hours of margin should be enough."

Yang Hui is still quite supportive of Director Bai's idea, but this spindle is not a little risky, and 1,350 hours is still very good, only 50 hours less than the economic life of the high-pressure compressor, which is still acceptable.

"That's not wrong to be conservative, the life of the two most important components is set at 1,350 hours, which is about the same as the total life of the engine. 1,350 hours is much better than the life of our Turbojet 7, almost twice the life of our Turbojet 7 engine. ”

The combustion chamber and the high-temperature turbine are still testing specific data, but Director Bai has great confidence in these two components.

"Now our combustion chamber and high-temperature turbine are already being tested, and the specific life span is unknown. But the first crack in the combustion chamber was in 400 hours, and now it has been 500 hours, and there have been no problems, according to our calculations, the first overhaul of the combustion chamber is about 600 hours, so that the first overhaul of our new engine is also scheduled at this time. ”

The combustion chamber is a high-temperature component, which is the most prone to problems, and the life has always been the shortcoming of the aero engine and the shortest shortcoming of the barrel effect.

"That's right, the director is really fast, the combustion chamber and the high-temperature turbine are all made, which is a little unexpected."

Yang Hui sighed, and so did Director Bai: "Yes, now we have been almost a year, we won this project in July last year, and now it is March, a full eight months, we are secretly revising the design outline, and it is not easy to conceal it for four and a half months." (To be continued.) )