The military-industrial scientific research system of the academic master.

the other side.

Xu Yang's work efficiency is indeed impeccable.

She previously promised to complete the simulation verification program of the digital control system within two days, but in the end it only took 46 hours.

From the outside, it just looks like two new signal input lines are connected to the surface of the engine that has been mounted and connected to various pipelines.

But in fact, based on the program that has been written and packaged, a random signal input time delay algorithm is plugged in to simulate packet loss or high delay during data transmission.

"Thanks a lot."

Chang Haonan looked at Xu Yang, who had disheveled hair and a tired look on his face, and said a special thank you for the first time.

"It doesn't matter, we can't delay everyone's progress..."

Xu Yang had been in an excited working state for nearly two days. Now that he relaxed, he was so sleepy that he could hardly open his eyes. He yawned and waved his hands:

"I will not participate in the subsequent testing sessions. I have to go back and catch up on my sleep."

"If there is a problem with the simulation verification program of the station, just go to my dormitory and knock on the door... But I think... it should... not..."

It was not a long sentence, but the speed of speaking slowed down at the end...

Of course, something as big as aero-engine test-running cannot be done as easily as eating and drinking.

After completing the final round of comprehensive inspections and confirming that the engine and test bench are properly prepared, Chang Haonan, Hai Yide, Li Rongzai and other turbofan 10 project leaders and the leaders of the 624 Institute still need to sign for confirmation respectively.

By the time the full set of procedures was completed and the aviation engine was officially launched, it would already be the morning of the next day.

As the technicians withdrew from the test cabin where the high-altitude platform was located, the thrust bench holding the engine moved slowly along the slide rail to the exhaust cooling device.

Compared with when Chang Haonan first came here two years ago, today's test station has been much optimized compared to the past.

The most obvious thing is that a complete camera monitoring system is set up inside the test cabin.

In this way, everyone in the control room can intuitively see the real-time images during the engine test, instead of just judging from the sounds reaching their ears and the dry data displayed on the computer as before. The working conditions of aviation development.

Moreover, you can also save the video by the way.

It can satisfy Chang Haonan's wish.

When testing the turbojet 14, Chang Haonan always wanted to leave some real image data. After all, it is the first domestic engine with independent intellectual property rights, and it will definitely leave a mark in the history of China's aviation industry.

Unfortunately, due to lack of relevant conditions, it ultimately failed to succeed.

During the entire bench test of the Turbojet 14, only a few blurry photos were left.

……

"Mr. Chang, it's up to you to give the order to start testing!"

Hai Yide, who was standing in the front row, gently pushed Chang Haonan and pressed the latter onto the chair behind the podium in the control room:

"This……"

In the presence of the chief engineer and chief division, according to general practice, the command command should still be given to the former.

However, Haiyide's tone was quite firm, and he had obviously already made plans.

At such a critical moment, it would be unsightly to get entangled over something like this.

Therefore, he immediately calmed down, took a deep breath, pointed into the microphone and said in a calm tone:

"The first test of prototype B0101 high-altitude platform, start!"

When I came to test the turbojet 14 and turbofan 9 before, those two models were not actually considered "new" engines.

This is not the case with Turbofan 10.

This B0101 machine has only been tested on the ground a few times under factory conditions.

Due to limited conditions, the traditional startup method was still used at that time.

This is now the first use of electric start.

Therefore, the testing process is naturally much more detailed.

"Roger, start!"

After receiving the order, the operator pressed the engine start switch on the console in front of him.

The display screen in the operating room shows six sets of pictures from different angles.

Compared with the sound and light effects of air-gas starting, the electric starting process is almost silent.

Although electric starting still uses air in the final step of pushing the starter, this process occurs in places where cameras cannot see it.

Similarly, the N2 speed of the high-pressure compressor will continue to increase during this process, but it cannot be observed with the naked eye because of the obstruction of the two-stage fans outside.

"Turn off the turbo heater and front starter!"

Chang Haonan issued the second order.

The principle of the aviation engine starting process is somewhat similar to that of a car.

Even many small aviation engines are started using a battery + P0 motor structure.

But for a high-thrust turbofan of the size of Turbofan 10, this kind of trivial work is definitely not possible, so an external power supply is needed——

For example, a power supply vehicle, or an auxiliary power system (APU) integrated in some aircraft.

In the bench test environment, these two components are not actually set up, but as a complete startup process, their existence still needs to be simulated in the test system.

On another monitor in the control room, various parameters captured by the sensor have also been displayed one by one.

Soon, the N2 speed reached the ignition fuel supply line.

"Combustion chamber, ignite!"

At this time, the engine finally had some obvious reaction.

As the operator rotates the starting handle, the aviation engine ignition nozzle generates high-voltage electric sparks in the combustion chamber, igniting the atomized fuel and the high-pressure air mixture that has just been sent into the combustion chamber by the compressor.

A faint flame emerged from the tail nozzle, but it only lasted for a moment.

It is not difficult to tell from the sound that the engine's operating speed is rising steadily.

At this point, the engine has officially entered working condition.

A burst of warm applause broke out from around Chang Haonan——

For an engine that is actually installed on the aircraft, the entire starting process will be completed automatically under the action of the flight control system.

But for the engine testing process, it is a high-risk subject.

From a mechanical point of view, the engine's transition from static to dynamic is a transient process, involving various non-periodic changes with huge fluctuations.

From a control perspective, it is an open-loop process. If there are loopholes in the control logic or algorithm, the working status may not converge.

Therefore, a smooth start is definitely a good start.

Taking advantage of this time, he also left his seat in front of the podium.

There are hundreds or even thousands of links in high-altitude platform testing, and naturally there are personnel specifically responsible for issuing command commands.

Chang Haonan, the chief designer, should focus on testing data.

The reason why I command the first three steps is to consider a symbolic meaning.

The engine's idle thrust finally stayed at 145 kilograms of force and did not change.

This number made many engineers at the 624 Institute who were exposed to the turbofan 10 for the first time show slightly surprised expressions.

After all, airplanes don't have gearboxes.

The high-temperature and high-pressure gas must be output through the tail nozzle, and the energy generated must be converted into thrust.

The idle state itself is not to "propel" the aircraft, but to maintain the minimum working state of the engine for stable operation.

From this perspective, the smaller the number that can be stabilized, the better.

The number 145 is already an extremely high level.

"Mr. Chang, how do you keep your engine running at such a low operating condition? Is there really no risk of stalling?"

Jiang Fuhe approached Chang Haonan and asked softly.

The latter slowly came to the screen displaying the test data, looked at the numbers on it, and answered at the same time:

"This is one of the benefits of full-authority digital control technology."

"Although whether the minimum steady-state thrust is larger or smaller will not directly affect the performance, and I have not specifically optimized this parameter, the electronic control system can inherently bring higher control accuracy and response speed, which is also beneficial to work. Fine adjustment of status.”

"It's just unintentional..."