When Chang Haonan met Haiyide in the test workshop, the latter was holding a walkie-talkie and instructed the on-site technicians to transfer the B0101 prototype from the special engine stand to the spreader of the aerial platform with a serious face.

Compared with the previous hydromechanical type, supplemented by some analog signal type aviation development control system, the turbofan 10 with full authority digital control capability looks much simpler in appearance.

A large number of hydraulic and pneumatic lines, which were originally used for control and operation functions, were eliminated and replaced with several engine control units and cables distributed around the aircraft.

In addition to reducing the reliability problems caused by these complex mechanical structures, it can also reduce the weight and cost of the engine.

Combined with the more concise 2-stage fan + 7-stage high-pressure compressor structure than the third-generation Hangfa, the national military standard weight of this engine was finally reduced to an astonishing 1560kg.

As a comparison, F110 and AL31F, two typical third-generation engines, have a dead weight in the range of 1750-1800kg calculated according to the national military standard.

Of course, 1560kg is still not the end.

The reason why the turbofan 10 is called the 3.75 generation engine is because although its structure has been almost infinitely close to the fourth generation, most of the materials and production processes are still at the level of the third generation engine.

After all, for Huaxia Aviation Industry, it was quite difficult to even produce the second-generation turbofan 9 before that.

Therefore, in order to ensure that the timeline of the project would not be affected by material problems, Chang Haonan did not adopt particularly aggressive weight reduction methods in the overall design of the casing and blades.

Typical fourth-generation engines, such as the F119, can even control their weight around 1450kg, thus achieving a theoretical thrust-to-weight ratio close to 11 at sea level.

That's the part to pursue, though.

Moreover, with the current capacity of the Dawn Plant, even after a comprehensive process upgrade, the speed of manufacturing turbofan 10 is still not optimistic.

After the hoisting step was over, Haiyide heard a slightly noisy footsteps behind him.

turned around, and just saw Chang Haonan who was leading people in.

"Comrade Haonan, long time no see."

The two shook hands.

According to the division of tasks, after the completion of component-level testing, the first engine was manufactured and assembled by him, the chief engineer, who was in charge of it.

This is also why Chang Haonan was able to spare time and go to Rongcheng for two months.

So after all, the two haven't seen each other for nearly a quarter.

For general projects, the chief engineer and the chief engineer take turns to go online and often do not see each other for dozens of days, which is likely to cause chaos.

But the situation of the turbofan 10 is special after all.

At present, almost all the test content can be successfully passed, wearing multiple hats does not seem to bring too much burden to Chang Haonan.

Naturally, no one would disagree with this without opening their eyes.

"We are still familiarizing ourselves with the improved test bench and expect the prototype B0101 to be ready for testing within two to three days."

Haiyide, who completed the command task, hung the walkie-talkie back on his shoulder, and then took Chang Haonan to the nearest place while explaining the current work progress:

"The main reason is that compared with before, there are a lot more backup gas-liquid action mechanisms that need to be connected in this test, not only us, but even the technicians of the 624 Institute are also getting it for the first time."

The latter looked up and watched as the field engineer on the operating frame began to carefully insert the pipes into the engine's vital locations as they checked the drawings.

Full digital control is a great upgrade for engines and aircraft, but correspondingly, it can be a lot more cumbersome during testing.

Because once the electronic control system is out of control, it cannot be shut down as simply as a purely mechanical equipment, and may even endanger the safety of the high-altitude platform itself.

In particular, the Turbofan 10 is the first model in Huaxia to plan to adopt this technology from the beginning of its design (it was tested on the Turbojet 7 earlier).

And now the pipes connected to the engine are to play an "external emergency backup" function.

Although the probability of such a serious accident is very small, provided that it passes the factory test, it is still a precautionary measure.

"It doesn't matter."

Chang Haonan waved his hand:

"Part of the time I picked out in the previous design tasks was intended to leave room for production and testing."

"There are always ways to improve some efficiency at the theoretical and computational levels, but when it comes to the material level, we still need to be cautious and respect objective laws."

"In addition, before the official start of testing, it is necessary to check the control rules of the improved bench system, which will take several days."

"I can't hold you back too much......"

Haiyide put his hands behind his back and said with some emotion:

"In the past, compared with foreign countries, I felt that our development speed was actually not slow, but after doing projects with you in the past two years, I always felt that there was a force behind me pushing forward."

"It's a shame to say this, they are all comrades in charge of the same project, how can there be any talk of delay, it's just normal to learn from each other's strengths."

Chang Haonan waved his hand, then rubbed his neck, which was a little sore from looking up for a long time, and turned his gaze back to Haiyide:

"By the way, Mr. Hai, how is the situation on the side of Project 11 during this time? Especially the verification machine for us? ”

Although it is not a system, the 601 and 606 institutes are in Shengjing, which can be regarded as brother units, and the Taihang project is actually a part of the No. 11 project, so some basic information can still be found.

Although he sometimes talks on the phone with Yao Mengna, who is almost always in Shengjing, it is impossible to talk about the project in it.

"The part of the assembly of the parts has almost been completed, and the next step is to gradually increase the localization rate from the seventh batch, and then replace it with new domestic airborne equipment."

Haiyide replied:

"As for the replacement verification machine, the 112 factory will set aside a two-seat J-11AS quota for us to carry out installation experiments, I also took a special look before coming to Fucheng this time, the body structure has been almost built, but the main subsystems have not been installed."

"The main reason is that the turbofan 10 is digitally controlled, so there will be a little difference between the pipeline layout and the flight control program and the current mass production type, and we have to wait until we send the next batch of B0201 prototypes over before we can continue the production process."

"If nothing else, it is expected that the test flight will be delivered by the end of this year."

There is no difference between the turbofan 10A and the turbofan 10B in terms of hardware, and they are even taken down from the same production line, except that the former limits the value of military thrust and maximum thrust at the control system level.

It's a bit like some car engines, as long as the external computer is swiped to the second level, you can unlock more performance.

In the sequence of archives within the aviation industry system, the two share the same production code, except that the Air Force distinguishes at the equipment level.

Therefore, all items except for the reduced life test are carried out with the benchmark model, and the A model does not need to go through the process again.

After chatting about this part of the topic, Xu Yang, who had just been waiting behind Chang Haonan, stepped forward:

"Next, let's introduce the simulation verification program of the digital control system, come with me, next door."

The group bypassed the high-altitude platform with dense cables and came to the control room that Chang Haonan was all too familiar with-

He's probably the person who's been in this room the longest outside of the 624 staff.

Xu Yang still didn't have any nonsense, and directly stuffed the information that had been prepared a long time ago into Chang Haonan's hands.

As for herself......

Pure off-draft, no need.

"The system adopts open-loop control for the engine starting process, taking into account the three starting modes in practical application, namely electric start, compressed air start and propane gas start, the high-altitude test and control system presets three different rules, namely fixed time program oil supply, speed function oil supply and appropriate oil and gas ratio oil supply."

"There is no one-to-one correspondence between them, and since the turbofan 10 uses full digital control, in most cases, the speed function should be used to supply the fuel, and the engine speed should be used as the linear mapping of the fuel flow......"

“……”

"The steady-state working process after the start adopts closed-loop control, considering that J-11 and J-10 will use the flight thrust integrated flight control system, this part does not need to consider the traditional physical speed control rate, directly adopts equal equivalent speed control, and the throttle command is directly sent by the flight controller through the communication port or in the form of PWM signals, so the specific algorithm is exactly the same as what you left in the ECU program, I will not repeat it......"

"In addition, there are some limit parameter limitations for safety considerations, including physical speed, command speed, T4 temperature, ......"

“……”

Xu Yang spoke for nearly two hours without interruption, obviously familiar with the test control logic he designed.

After it was all over, she picked up the thermos cup next to her and took a sip of water:

"Do you think there's anything else you need to add?"

Obviously, she is very confident in the results of her work.

However, Chang Haonan did not give an answer immediately, but stared at the part of "modeling the control object and actuator of the system" for a long time.

After ten minutes, he finally raised his head again:

"I want to ...... There should still be. ”

(End of chapter)