Chapter 629 Turbofan 10, ignition successful!
The other side.
Xu Yang’s work efficiency is indeed incredible.
Previously, she 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 is just two new signal input lines 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.
“Thank you for your hard work.”
Chang Haonan looked at Xu Yang, who had disheveled hair and a tired look on his face, and thanked him for the first time.
"It doesn't matter, we can't delay everyone's progress..."
For nearly two days before, Xu Yang was in an excited working state. Now he relaxed and felt sleepy. I could hardly open my eyes, yawned and waved my 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 be ...No..."
It was not a long sentence, but the speed of speaking slowed down at the end...
An aircraft engine test run is such a big thing, of course it cannot be compared with eating and drinking. Just do it as you say.
After completing the last round of comprehensive inspection and confirming that the engine and test bench are properly prepared, Chang Haonan, Haiyide, Li Rongzai and other turbofan 10 project leaders and leaders of the 624 Institute still need to sign separately confirm.
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 to when Chang Haonan first came here two years ago, the test station today 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 testing process, instead of only the sound reaching the ears and the display on the computer as before. Use dry data to judge the performance of Hangfa.
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 keep 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, it failed in the end due to lack of relevant conditions.
The entire bench test process of Turbojet 14 only left a few blurry photos.
...
“Mr. Chang, it’s up to you to give the order to start the test!”
Hai Yide, who was standing in the front row, gave Chang Haonan a gentle push. The latter pressed on the chair behind the command 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 Leave it to the former.
However, Haiyide's tone was quite firm, and he had obviously already made plans.
It would be unsightly to get entangled in such a critical moment.
Therefore, he immediately calmed down, took a deep breath, pointed at the microphone and said in a calm tone:
"The first test of the high-altitude platform of the B0101 prototype, start!"< br>
When I tested the turbojet 14 and turbofan 9 before, those two models could not be 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.
Now this is the first use of electric starter.
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.
On the display screen in the operating room, six groups of pictures from different angles are displayed.
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 by 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 instruction.
The principle of the aviation engine starting process is somewhat similar to that of a car.
Even many small aviation engines are started with a battery + P0 motor structure.
But for a large-thrust turbofan of the size of Turbofan 10, this kind of trivial effort will definitely not work, so an external power supply is required -
For example, a power supply car, or integrated in some aircraft Inside the auxiliary power unit (APU).
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 beside Chang Haonan——
For an engine that is actually installed on an aircraft, the entire starting process will be controlled by the flight control system. Completed automatically.
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 moment, he also left the seat in front of the podium.
There are hundreds or thousands of links in the high-altitude platform test, and naturally there are personnel 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 idle thrust of the engine finally stayed at 145 kilograms of force and no longer changed.
This number made many engineers from 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.
High temperature and high pressure gas must be output through the tail nozzle, and the energy generated must also 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 extremely high.
"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 in a low voice.
The latter slowly came to the screen displaying the test data, looked at the numbers on it, and replied 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 any performance, and I have not specifically optimized this parameter, the electronic control system can inherently bring higher control accuracy and response speed. It is also conducive to the fine adjustment of working conditions.”
“It’s an unintentional intervention...”
(End of this chapter)