August 31, 2015

For the Xinghai Group aero-engine project team, today is a milestone record.

At nine o'clock in the morning, Mu Yang came to the engine ignition test workshop.

Han Li and hundreds of people from the project team are waiting for the chairman's arrival, and everyone is looking forward to the success of the ignition test.

Success or failure is today.

"Have you finished the inspection?"

Mu Yang came to the scene and glanced at the hundreds of expectant employees. When he saw Han Li, he nodded to him.

Han Li took two steps forward to the chairman and said respectfully: "Chairman, the inspection is completed. You can ignite the test at any time. Please accept it."

His tone was 30% excited, 70% nervous, and he was under a lot of pressure. Months of hard work just seemed like today.

Mu Yang nodded, and Han Li walked into the ignition workshop to check the afterburner system, electronic system, vector system, etc.

In particular, afterburner ignition is the most prone to problems, which involves the afterburner fuel flow regulator, acceleration overflow valve, catalytic igniter, flow sensor, etc.

This engine adds ternary vector nozzle technology. The engine tail nozzle can swing in all directions, unlike the binary vector which can only swing up and down. Of course, this does not mean that ternary is better than binary. The application characteristics are just different.

A fighter jet equipped with a vector nozzle can deflect the nozzle and change the thrust direction to achieve attitude control of the aircraft, which is also one of the technical requirements for vertical takeoff.

For aircraft that do not use thrust vectoring technology, the jet flow of the engine coincides with the axis of the aircraft. Civil aviation aircraft and fourth-generation or lower fighter jets do not use vector nozzles.

Civil aviation aircraft pursue economy and cost, and there is no need to install vector nozzles.

This does not mean that using a vector nozzle is good. The vector nozzle increases the structural complexity of the engine because it has to turn, resulting in a loss of thrust and a considerable increase in engine weight.

The benefits are also obvious: the attitude is changeable, which significantly improves the fighter's maneuverability and technical and tactical performance such as vertical and short takeoff.

Mu Yang checked for about twenty minutes and found no problems before walking out of the workshop.

"Start the ignition test."

When Han Li heard the chairman's instructions, he looked solemn and shouted to the test personnel:

"Check site No. 1!"

The scientific researchers responsible for the on-site inspection observed with the naked eye that there were no people on site, and no life was found in the testing equipment. At the same time, the experimental door was shown to be closed.

"Report, site No. 1 is safe and can be tested."

Two scientific researchers reported loudly.

"start testing!"

Following Han Li's order, the tester turned on the control system and cooling system. After seeing that a series of instruments and indicator lights showed normal, he reported that everything was normal and could proceed to the next step.

This time the test ignition was directed by Han Li.

After Han Li glanced at the chairman, he solemnly shouted: "Start the ignition! Vector horizontal angle, running at 10% power."

As the tester pressed the start button, the engine "buzzed", indicating that the ignition system was operating normally and that the first step of work was completed.

The first thing to test is the test condition when the vector nozzle is in a horizontal state. Now we only need to test the ignition condition.

After a few minutes, the tester reported the situation.

"Report, normal operation without abnormality."

Han Li nodded: "Record the data and gradually increase the power!"

There is no problem in the XH-AN05-01 engine test. Han Li believes that there will be no problem when the Jun engine does not have afterburner.

Therefore, there was no expression of excitement on Han Li's face. Instead, he was a little worried. He was really afraid that the engine would not be able to withstand it after turning on the afterburner.

Even if he follows the entire development process, no one is sure if he hasn’t tested it yet.

Twenty minutes later,

After the power reached 50%, a strong wind blew up behind the engine, making the entire workshop very noisy.

The available work of the engine is the kinetic energy difference between the inlet and outlet airflow. The greater the thrust, the greater the wind force behind the engine.

Wind force F=PA, that is, wind pressure multiplied by area, is approximately equal to thrust.

With a thrust as large as the XH-AN05-01J, the pressure is very high. If the afterburner is turned on, it can blow people away from more than ten meters away.

On the aircraft carrier, when the aircraft is preparing to take off, a deflector baffle is raised about ten meters behind to block the flow. This is to block the high-temperature and high-speed gas ejected from the engine when the aircraft takes off, so as to prevent personnel behind the aircraft from accidentally entering and injuring the aircraft.

Now that it has just been ignited, the speed is very slow and there will be no afterburner.

Afterburner can only be turned on when the engine speed is greater than 80% NH.

The afterburner design range of XH-AN05-01J is relatively large, from 5% to 65%, which can be adjusted with micro-control, or can be quickly adjusted in six levels of 5%, 15%...65%, which is very convenient.

The percentage here is actually the percentage of increased thrust.

Afterburning is to increase thrust. The principle is to reheat the exhaust airflow to further accelerate the airflow and inject fuel into the afterburner to increase the combustion rate.

Of course, afterburning is equivalent to adding a nitrogen acceleration system to a sports car, which consumes a lot of fuel.

Therefore, fighter jets generally only use afterburner under special circumstances such as takeoff, landing, acceleration, etc.

Like the F-14A fighter jet, the maximum internal fuel capacity is about 7348 kilograms. If all afterburners are turned on, the fuel consumption per minute is about 907 kilograms, and all the fuel can be consumed in 8 to 10 minutes.

Moreover, it is easy to burn out the engine if it is turned on for a long time.

No matter how good the fuel economy of the XH-AN05-01J engine designed by Muyang is, if all the afterburners are turned on, it will be used up in just ten minutes.

However, if only a small part of the afterburner is turned on, such as 30% afterburner, it can last for half an hour, but it cannot be turned on continuously, otherwise it will easily burn the engine.

At this time, the XH-AN05-01J engine gradually increases its speed and power, and the noise in the workshop and the wind speed behind the engine are also increasing.

Every 10%, scientific researchers record experimental data and check whether there are any abnormalities in various instruments and equipment.

"Report, the thrust is 144KN and the operation is normal!"

When the power is turned on to 100%, the tester reports the data.

At this time, afterburner has not been turned on.

The main design performance parameters of XH-AN05-01J are: the maximum afterburner thrust is required to be more than 19 tons, the full power thrust without afterburner is more than 13.5 tons, the temperature in front of the turbine is 1520 degrees Celsius - 1720 degrees Celsius, and the weight is 1400 kilograms.

The actual situation is that the prototype weighs 1,410 kilograms, and the dimensions are certainly in line with the drawings, but some parts have errors, so the weight has changed.

At this time, the full power without afterburner has reached 144KN, about 14.7 tons, and the converted thrust-to-weight ratio is 10.5!

10.5!

All the people on site were very excited to achieve this figure without adding force.

Mu Yang took a look at the fuel consumption and found that it was not much different from the design.

"Maintain it for ten minutes and record the data!" Han Li ordered.

"yes!"

The R&D personnel responsible for control answered loudly.

Mu Yang's face was still calm. This did not mean that the ignition was successful. The afterburner was not turned on.

Time passed very quickly, ten minutes ended quickly.

The engine was running stably. After Han Li glanced at the chairman and saw that his expression was calm, he gave a new order:

"Afterburner 5%, pay attention to the temperature of the vector nozzle and afterburner!"

"yes!"

After receiving the order, the tester started to activate the afterburner system, and added more force when the afterburner was not at full power.

Suddenly, the oil pipe of the oil supply device supplies oil vigorously, oscillating combustion occurs in the afterburner chamber, the air pressure suddenly increases, and the temperature rises.

There is already an obvious red and yellow tail flame at the tail of the vector nozzle. It is daytime at this time, and you can't see it clearly if you don't watch carefully.

But if it is night, you can clearly see the bright tail flame.

"Report, the thrust is 151.1KN and the operation is normal! The temperature in front of the turbine is 820 degrees Celsius...850 degrees Celsius...Fuel consumption..."

"10% afterburner for five minutes!"

"Report, the thrust is 158.8KN and the operation is normal! The temperature in front of the turbine is 950 degrees Celsius... 1010 degrees Celsius... The fuel consumption increased by 14.5%..."

"Turn off the heat and cool down! Record the data and check the equipment."

Afterburning continued for five minutes, Han Li called for the engine to be turned off, allowing his subordinates time to record data and conduct inspections.

Turn off the engine for about a minute and start the afterburner again.

"15% afterburner for five minutes!"

"Report, the thrust is 166.7KN, and the operation is normal! The temperature in front of the turbine is 1050 degrees Celsius... 1110 degrees Celsius... The fuel consumption has increased..."

…

"Afterburner 50%, lasts 120 seconds!"

"Report, the thrust is 223.2KN, and the operation is normal! The temperature in front of the turbine is 1420 degrees Celsius... 1515 degrees Celsius... The fuel consumption has increased..."

At this time, with the afterburner reaching 55%, the thrust has reached a terrifying 22.32 tons, exceeding the design requirements. The fuel consumption has soared, and the temperature has risen very quickly, and the color of the cylinder has turned red.

If ordinary steel is used, this temperature has already reached the melting temperature. Not to mention above 1420 degrees Celsius, the material can be softened and damaged at 1200 degrees Celsius.

In fact, when the afterburner reaches 30%, the thrust has reached the design requirement of 19 tons, which is far beyond Mu Yang's expectations. The fuel consumption at this time is that it can drive for more than half an hour with full fuel. It can be said that it is casual.

However, the test will overload the running tests.

After completing the test with 60% afterburner, turn off the flame and cool down for one minute.

In an emergency, it doesn't take that long to cool completely, so it needs to be used frequently.

"Afterburner 65%, lasts 30 seconds!"

When Han Li issued this order, everyone was very nervous. This was the highest requirement for the experiment.

Whether it succeeds or not depends on these 30 seconds.

"Report, the thrust is 238.0KN and the operation is normal!

The temperature in front of the turbine is 1620 degrees Celsius... 1715 degrees Celsius... The cylinder is overheated, the temperature alarm is triggered, and it automatically shuts down, and it can only last for 22 seconds."

As the tester reported, Han Li sighed: "Hey, it's still a little short of the mark."

This engine is equipped with a temperature monitor. If a certain component is overheated, it will continuously alarm. If the automatic control mode is turned on, the afterburner will automatically shut down.

If the alarm continues to turn on, the engine combustion chamber and cylinder will be damaged.

"Chairman, it still failed."

Mu Yang smiled, patted his shoulder and said, "It's not considered a failure, it has exceeded my expectations.

It’s just a bit regretful that the afterburner time did not meet the design requirements. Let’s optimize it slowly.”

238KN, which is equivalent to a thrust of 24.2 tons. The main design parameter afterburner-thrust-to-weight ratio reaches a terrifying 17.1!

Of course, it can only last 22 seconds.

No!

This shouldn't be the case!

If you don't turn on the automatic control mode and don't worry about the engine burning out, it should be more than 22 seconds.

Definitely lasts longer!

However, in this case, the vector nozzle is in a horizontal state. If it is pointed downward, the temperature will rise faster due to the reverse thrust and will not last that long.

If the engine is put into service without optimization, Mu Yang thinks that the maximum design afterburner is 50%, and it can be used continuously for more than 120 seconds.

During the test just now, the maximum temperature was still far from the warning line temperature.

And after 120 seconds, the temperature continues to rise very slowly, indicating that it is basically stable.

Of course, this level of 50% afterburner consumes a lot of fuel. The fuel consumption per minute is about 400 kilograms. If it has an 8-ton fuel tank like the F35, it can drive for 20 minutes when fully loaded with fuel.

If the battle cannot be resolved in 20 minutes, there will be no fuel left to return.

In actual combat, the afterburner time will not last that long and will be intermittent.

In addition, fighter jets are also equipped with auxiliary fuel tanks to increase the fuel capacity. Generally, auxiliary fuel tanks can carry several tons of fuel.

at this time,

When Han Li heard the chairman's comfort, he felt a little more relaxed and breathed a sigh of relief.

It is true that other engine research institutes may not be able to develop it, and it is impossible to successfully ignite it the first time. It may take several years to successfully develop it.

Mu Yang added: "See how much fuel is left, and test whether the maximum duration can burn 8 tons of fuel with 50% afterburner. Also test the duration.

However, you should first check whether the equipment is burned out, and if there is no problem, you can conduct a test."

Han Li was startled for a moment and soon understood what the chairman was thinking.

"Enough, there are 55 tons of fuel left."

However, it was already lunch time at this time, so we could only postpone the inspection until the afternoon.

It takes a long time to check the engine. If you have to check it all, it will take at least a few days to sort out the test data.

In addition to the ignition test, there are many tests to be tested, and they are destructive tests, such as water absorption test, ice impact test, flying animal impact test, and tests with blade loss. These tests will directly cause the engine to be scrapped and require

It costs a lot of engines.

Engine testing is so expensive, and testing money is a bottomless pit.

After the successful ignition test of the civil aviation engine XH-AN05-01, more than 20 prototypes have been manufactured for testing. The testing cost in the past few months has cost hundreds of millions of yuan.

The morning test ended like this, and Mu Yang left the testing site happily.

Today's test was a bit regretful, but it was pretty good. I was most afraid that it couldn't even start the ignition.

The next engine test period will be very long, and Mu Yang plans to take a look when he has time.

The XH-AN05-01J engine is so powerful. Without afterburner, the thrust-to-weight ratio reaches 10.5, and the maximum afterburner reaches 17.1!

Compared with the F135-PW-100, the world's most powerful turbofan engine currently in service, its thrust-to-weight ratio is 7.47, its thrust-to-weight ratio at full afterburner is 11.47, its net engine weight is 1,701 kg, its transition thrust is 12.7 tons, and its maximum afterburner thrust is 19.5

Ton.

It serves on the F35 with an empty weight of 13.3 tons, a maximum take-off weight of 31.8 tons, and uses a single engine.

The XH-AN05-01J is much more advanced than the F135-PW-100, weighing only 1,410 kilograms, but its transition thrust reaches 14.7 tons and its maximum thrust reaches 24.2 tons. This also means that the fighter jet equipped with it can carry heavier cargo.

, it flies faster and is more flexible due to the use of a three-dimensional vector nozzle.

When sleeping at night, Mu Yang had a dream.

He dreamed that he was on a J-20, and the engine was equipped with XH-AN05-01J, the latest military engine from Xinghai Group.

He looked around and saw an ocean!

The plane is on the country’s aircraft carrier!

Hey, how do I sit on the cab?

I don’t think I’ve ever flown a plane, right?

It's not like he has never flown a plane before.

However, with his knowledge of aircraft, he was able to understand the aircraft's instruments and operating methods. When he held the control stick, he felt a sense of familiarity and a good feel.

strangeness.

"Mr. Mu, you are ready to take off."

Mu Yang heard the takeoff commander's order on the aircraft carrier deck and saw the expectant looks of hundreds of people on the deck.

Before he had time to think, he turned the engine on to 80% horsepower, and instead of relying on the ejection booster, he used a ski jump to take off. The takeoff and starting distance was relatively long, and it relied heavily on the performance of the aircraft. If it was any worse, it would fall directly into the sea.

After releasing the brake, the J-20 rushed forward quickly. He felt a difficulty breathing instead of a powerful thrust.

At the same time, in just half a beat, he immediately reached full throttle and full afterburner.

After only running a few dozen meters, the J-20's speed increased rapidly, and he discovered that it could take off even without a ski-jump deck.

However, he couldn't allow him to think too much. The plane rushed over the ski-jump deck and took off into the air. It didn't have a tendency to fall, but went straight up.

Hundreds of people on deck applauded enthusiastically.

However, just as Mu Yang continued to pull up and take off, the aircraft seemed to be out of its control, and the afterburner system could not be turned off. No matter how tightly he held the control stick, it was useless, and then it fell headlong into the sea.

The moment he fell into the sea, he thought of his family.

Mu Yang was frightened and opened his eyes suddenly, only to realize that he had had a nightmare.

My head was covered with a quilt, no wonder it was a little difficult to breathe...

"Fuck you!"

"this……"

"No wonder."

Fortunately, the child is not sleeping next to me tonight, but my wife is sleeping next to me.

It seems that I haven't done gymnastics for a long time. I saw that the time is already 12 o'clock in the morning.

"Honey, are you asleep?"

Song Xuelu just murmured Mu Yang's question and seemed not to have died of sleep.

He breathed a sigh of relief and just didn't sleep. He didn't ask for his wife's opinion and started to make small moves.
Chapter completed!