Chapter 1087 Titanium Alloy Hollow Fan Blades

Although no direct results were given, as long as it reaches the stage of being discussed with superiors, it basically means that the problem is not serious.

Especially when the technology itself has been proven on the ground and in the air.

The topic of conversation quickly turned to a more specific level.

After all, for a satellite, especially a small satellite weighing hundreds of kilograms with limited frequency band resources and energy supply levels, there are many issues that need to be considered in addition to the core functional modules.

For example, cross-layer adaptive transmission, Doppler change rate estimation algorithm, Ka-band satellite channel model, and tilt estimation algorithm, etc.

Not to mention at the beginning of the 21st century, even in another twenty years, the large number of tiny satellites launched will have their failure probability calculated before entering orbit, and then be launched with redundancy.

But Chang Haonan and his team only have four test constellations this time, and they definitely cannot withstand any accidents.

Fortunately, Lin Senming and Zhang Weiyong were originally from the field of satellite design, and they had already considered all these aspects thoroughly.

Guo Lin was also happy to reduce his presence at this moment.

Unless the question is related to your business, you will remain silent.

Therefore, this meeting quickly came to an end.

However, just after leaving Luan Wenjie's office, he was stopped by Shen Junrong who came out with him.

"Comrade Guo Lin, please wait a moment!"

After all, Guo Lin is from a brother unit, so Shen Junrong is quite polite towards him.

The three of them stopped at the same time and turned to look at the latter who was holding a briefcase and coat.

Seeing their fearful expressions, Shen Junrong smiled and waved his hand, signaling them to relax:

"Don't be nervous... We've already finished talking about the main business. I just want to ask a few more questions about personal interests."

That being said, Guo Lin couldn't really take this as idle chat:

"You say."

As an expert in the field of aerospace measurement and control, Shen Junrong is naturally most interested in his old profession:

“I remember you just said that because this constellation only corresponds to individual spacecraft and ground terminals, there is not much pressure on the frequency domain and beam pointing?”

"Yes."

Guo Lin nodded:

"Due to the size of the satellite, we only set up two downlink channels and four uplink channels on each satellite, but combined with the new attitude determination algorithm, it is expected that the communication requirements of this test can still be met."

In fact, Guo Lin did not tell Chang Haonan's entire plan.

The four-star constellation is expected to operate effectively for more than a year.

After completing the relay communication mission for Shenzhou V, it will return to its original design purpose.

That is to provide a wider image return window for the Ocean No. 1 satellite.

Or it only serves individual objects.

It is expected that the data transmission time can be increased to 6-8 hours per day.

Of course, because the communication rate of Ocean No. 1 itself is very slow, it is impossible to reach the theoretical performance limit of the relay constellation.

But it is enough to avoid the situation at the beginning of the year where "a lot of useful information was captured but it took multiple cycles to transmit it", affecting the timeliness of reconnaissance information.

However, this answer obviously did not solve Shen Junrong's doubts:

He gestured for everyone to move forward together and continued:

"When I was in the Science and Technology Commission, I had some contact with Advisor Chang. He doesn't seem like the kind of person who only looks at the present..."

"You have put so much effort into relay communication verification, from airships to airplanes and then to satellites. So your ultimate goal in the future cannot be to just provide services to a few spaceships or satellites, right?"

"When the number of users increases, won't we still have to solve the problems of frequency domain range and pointing flexibility?"

I can only say that people who have led large projects do have a different perspective.

He saw through Chang Haonan’s long-term goals at a glance.

In fact, the other three people were not clear about this question either.

Zhang Weiyong knew that Chang Haonan's original purpose in planning the relay communication constellation was to form a global space-based remote sensing system with a revisit period at or below the daily level at the lowest possible cost.

Moreover, it takes into account multiple levels, including tactics and strategy, military and civilian use.

Taking into account the diversity of usage environments and the fact that there are many types of remote sensing satellites themselves, it must be a very complex network as Shen Junrong said.

However, Chang Haonan never revealed how to achieve it technically.

However, Guo Lin, who was standing by, gave an answer after thinking for a while:

"We did not apply for the commonly used but crowded L/S/C bands, but chose the Ka band, which is currently less used. We took this into consideration. Another thing is..."

Having said this, he hesitated, as if trying to decide whether to continue.

But in the end he continued:

"Although Mr. Chang has not mentioned it explicitly, I personally guess that... it may also be related to the new wide-bandwidth and wide-angle phased array technology we are currently testing."

The ground testing of optically controlled phased array radar has been going on for almost two years. It has demonstrated many advantages, such as light weight, low heat generation, high beam pointing accuracy, wide frequency domain range...all of which are very suitable for use on satellites.

It is natural for Guo Lin to make such a speculation.

When Shen Junrong heard the description of "new phased array technology", he knew that the other party was referring to the optically controlled phased array.

He had overheard this from the leader of China Electronics Technology Group Corporation during an industry meeting.

However, Shen Junrong did not delve further into the matter.

Although the whole country is working as one, we are not part of the same system after all. It is impossible for us to reveal all the details to you just because we have a cooperative relationship.

Continuing to ask without any caution will only lead to embarrassment for both parties.

Coincidentally, the four of them also walked to the entrance of the building.

He took the opportunity to say goodbye to the three people and asked them to submit the plan as soon as possible...

……

While comrades from several brother units were busy because of his advance planning, Chang Haonan himself had also completed a series of preparatory work after the project was launched.

Generally speaking, the research and development work officially begins at this stage.

However, the projects managed by Chang Haonan still conform to his past habits——

During the preliminary research phase, tasks had already been assigned to each unit, and they had even begun work on some key technologies.

Therefore, less than a month after the AE1500/WS-20 project was launched, Chang Haonan convened the two departments responsible for production and testing to hold the first sample production seminar.

Of course, it does not refer to the whole machine sample.

Not even a component level sample.

Even if there is a system cheat, it is still too outrageous to come up with complete design parameters in one month.

In fact, it can only be regarded as a prerequisite for fan testing.

However, although it is a prerequisite task.

But the difficulty is not low at all...

In the conference room, Chang Haonan was sitting at the head of the conference table, leaning sideways to look at the blade design displayed on the screen behind him.

"In the design, we tried to increase the relative chord width by more than 40%, which greatly improved the aerodynamic efficiency of the fan blades. While enhancing the rigidity of the blades, we also weakened the vibration intensity under high-speed rotation. As a result, we removed the boss in the middle of the blade body in the design, which reduced the difficulty of manufacturing the outer contour of the blade..."

"..."

However, on both sides of him, the other dozen technicians looked embarrassed.

Compared with the fan designs they have come across before, whether it is WS-9, D436 or PS90A, the current solution is very different.

The wide chord design does reduce the difficulty of manufacturing the outer contour.

However, using titanium alloy materials to make a large, backward-curved, swept blade means that the basic difficulty is extremely high.

And isn’t the nearly 40% internal hollowness a bit too outrageous?

Due to the excessive void ratio and the fact that Chang Haonan did not adopt an aggressive blade pre-deformation design, a large number of triangular trusses were designed inside the fan blades to ensure strength.

It is a nightmare in CNC machining...

After the introduction, Chang Haonan turned around and saw the embarrassed expressions of his comrades in front of him.

However, he smiled instead:

"Don't be so sad... I know this blade is something you've never seen before, and it will use a lot of new technologies and concepts... But I have basically planned the production route for the samples."

After hearing what Chang Haonan said, the atmosphere at the scene finally relaxed a little...