For a brand-new engine like the turbofan 10, the process of high-altitude platform testing is still complicated.

It took nearly a week to complete the various 0-altitude ground conditions, from slow trains to low rpm conditions.

This is again when all the projects are done and there are almost no surprises.

"Mr. Chang, you should start measuring the speed today, right?"

Jiang Fuhe looked at Chang Haonan, who was directing the technicians to adjust the test data, and his tone revealed a little eagerness.

Although there are many different performance indicators of aero engines, it is impossible to describe the performance of one or a few numbers alone.

But even an industry insider like him can't avoid paying attention to performance such as mid-thrust and maximum afterburner thrust.

It can even be said that from the first day this B0101 prototype was shipped to the 624 Institute, Jiang Fuhe has been looking forward to it.

After all, this is a key indicator for grading aero engines.

"Well, today I will gradually increase the speed to the maximum in stages, and if the minimum continuous stability time can be met, then the working condition of the afterburner will also be done, but strictly speaking, I am afraid that it will be ......."

Chang Haonan turned his head and glanced at the watch hanging on the wall next to him:

"I'm afraid it won't be done until early tomorrow morning."

Speaking of which, he rubbed his temples that were a little swollen from continuous work:

"If it goes well, we should be able to complete the sea level performance by the end of August, and then gradually increase the simulation height, and the pressure can be slightly smaller......"

While the two were talking, the test over there had already begun.

Unlike the slow driving conditions tested in the previous days, the sharp roar of the engine can be heard even in the control room when the compressor speed is raised.

Although it was not deafening, it also made Jiang Fuhe can't help but raise the volume of his speech:

"Mr. Chang is still humble."

He shook his head:

"To be honest, these projects you have presided over should be the ones I have seen in my more than 30 years of work, whether it is R&D or testing, the process is the smoothest......"

"I don't remember that there has been any rework, including the previous Turbojet 14, although it was repeated a few times in the middle, but it was all in the early years, after you got involved, it was almost logical to go all the way to the finalized ......"

In fact, before Chang Haonan came over, Jiang Fuhe even had a little tangled idea of wanting to see the other party's jokes.

Mainly, he felt that the former was a bit unreasonable.

In industrial design, many times the initial parameters are guessed by experience, and then continuously adjusted and iterated according to the test results.

It's normal to have a few iterations along the way.

Just as social progress spirals.

On the contrary, it is a situation that can only be encountered by luck in the past.

It shows that the parameters at the beginning are well chosen.

However, Chang Haonan completely pressed these common senses of the past to the ground and rubbed them.

How can he have any spiral in these projects?

It's all going straight up like a rocket!

Jiang Fuhe is not a person behind closed doors, so he has naturally tried each other's research methods and tools such as TORCH Multiphysics.

It turned out that although the work efficiency has indeed improved dramatically, to put it bluntly, it is still the same set of iterative calculations, but the spiral speed is faster.

It is far from the magic level of being able to pass the test shop directly from the drawings.

So he thinks that Chang Haonan's level is not very reasonable.

Ten or even nine points are unreasonable.

If you have been relying on strong luck before, then no matter what, when it comes to a project as complex as the turbofan 10, there should be enough risk accumulation, right?

And if it weren't for luck......

Then Jiang Fuhe was about to start wondering if there was something wrong with his worldview.

And now the test has been going on for a week.

The results are clear.

Chang Haonan didn't lose, but he lost the worldview......

Thinking of this, Jiang Fuhe sighed:

"Sometimes, Mr. Chang, you give me the feeling that you are not doing research and development of a new model, as if you have directly brought a mature model."

He may not have imagined that this unintentional sentence is actually infinitely close to the truth......

In fact, when Chang Haonan is doing other small projects, the process is similar to others, and it takes continuous trial and error to find the correct design range.

At most, it's about having more experience to make the process a little faster and not trying to make a big mistake.

However, in key projects such as turbofan 10 and die forging presses......

He's open.

As Jiang Fuhe just said, the system can provide all the parameters of a mature model.

It's just that except for the time when I was in a hurry to design TORCH Multiphysics, I didn't just take out the results directly, but had to go through the development process again......

If you really want to talk about it, for today's Chang Haonan, there are only a few projects that are directly opened.

However, the vast majority of people will only focus on these kinds of big projects.

As for such "small" jobs as the Air Police 200 AWACS aircraft, many times he will not even hang his name in a conspicuous position, and not many people can know it at all.

For the work done in the name of the Torch Group, it is impossible for outsiders to know the specific division of tasks.

As a result, what impressed everyone was only these open parts......

"What ...... this?"

Chang Haonan touched his chin:

"On the one hand, there is the luck factor, and on the other hand, ...... Perhaps I have a special talent for being unexpectedly accurate when it comes to choosing design parameters. ”

"But this kind of thing is still unreliable in the end, so no matter what happened in the past, there should be no less testing process to follow, otherwise it will be troublesome if something goes wrong......"

He couldn't directly admit that he was hanging, so he had to explain it with "special talent".

"Okay......"

Jiang Fuhe was stunned for a while, and finally sighed a little helplessly.

It's the foundation of the worldview......

……

Today's testing process is just as smooth as before.

Originally, the speed of the aviation engine should be a more thrilling process.

Whether it is in China or abroad, if there is any major problem with most of the airlines, such as fire and explosion, it basically happens in this process.

But in the turbofan 10, it is monotonously a little sleepy.

If it weren't for the continuous high-frequency roar in his ears, Jiang Fuhe might really have fallen asleep.

After all, after the high-altitude station equipment was turned on, whether it was command or operation, it had nothing to do with him directly.

20%……

40%……

60%……

80%……

As the engine entered the experiment again and again, the N2 speed pushed by the high-pressure compressor continued to increase, gradually approaching the upper limit of the set working speed.

On the screen showing the test data, the thrust curve also went up from 145 kgF at the beginning.

In the end, without turning on the afterburner, the stable sea-level thrust corresponding to the maximum speed stayed at 8410kgF.

8.41 tons!

"Hiss......"

Looking at the thrust value on the screen in front of him, which was stable to close to a straight line, Jiang Fuhe was suddenly shocked and sobered up:

"So accurate?"

As an aviation designer, he was more surprised by the consistency between the actual test results and the paper values in the design process than the inferred value of 8.4 tons itself.

Jiang Fuhe clearly remembered that before the test, he was sent to the estimated parameter manual of the 624 Institute with the prototype B0101, and the intermediate thrust was calibrated at 8400kgF.

The difference of 10 kilograms can be regarded as a negligible test error.

"That's ......"

He turned his head a little stiffly and looked at Chang Haonan, who was standing not far behind him:

"Mr. Chang, the thrust-to-weight ratio of your 'thrust-to-weight ratio 9 first-stage turbofan engine'...... I'm afraid it can't really reach 9, right? ”

"Huh?"

The latter had been spinning for a day, and when he was suddenly asked like this, he didn't react a little:

"That'...... Or else? ”

Jiang Fuhe was also blindsided by this rhetorical question.

It took a while before I came back to my senses:

"Regardless of domestic and foreign countries, generally speaking, the thrust weight ratio is 9 level, and the default is between eight and nine, and after 9, it is said that it is a 10 level of thrust weight ratio...... After all, it is necessary to leave room for publicity for subsequent improved models. ”

"Just like the AL31F and F110 engines, although they both claim to be a thrust-to-weight ratio of 8 levels, the actual thrust-to-weight ratio of the basic model is only about 7.0 and 7.3 respectively according to our national standard, and it is not until the new sub-model in recent years that it has really reached the thrust-to-weight ratio of about 7.6."

"But this turbofan 10...... Although the afterburner has not yet been opened, I estimate that according to your calibration accuracy, the actual maximum afterburner thrust should really be 14 tons......"

(End of chapter)