Great Country Academician

In the field of aerospace, heat insulation and heat dissipation are extremely important in the thermal system of spacecraft, and are also related to the safety of spacecraft and even astronauts.

Whether it is the thermal cycle and heat dissipation work inside the spacecraft, or the heat insulation work outside the space shuttle during launch and return, they are all difficult problems in the aerospace field.

Especially when the return capsule of a space shuttle or manned activity returns to the ground, especially when it passes through the dense atmosphere at an altitude of 80 kilometers to 40 kilometers above the ground at a speed of several meters per second, the surface temperature of the return capsule will reach 1000-2000 degrees Celsius, or even higher.

If effective heat prevention and cooling measures are not taken, the entire return capsule will be burned to ashes like a rock.

For example, when the American space shuttle Columbia returned to the ground, its surface temperature exceeded 2,000 degrees.

During the crash, high temperatures exceeding 1,500 degrees poured into the interior of the space shuttle from the gaps in the insulation tiles, killing all seven astronauts on board.

This was an extremely tragic aerospace accident, but what is even more tragic is that aerospace disasters caused by various small problems are not uncommon in the development of aviation in countries around the world.

Xu Chuan didn't want such a disaster to happen in his own hands, so the problem of the Xinghai's outer insulation tiles was a problem that had to be solved.

Staring at the report data in his hand, after thinking for a while, he looked up at Weng Yunzong and asked, "Do you have a solution to this problem?"

Weng Yunzong shook his head and replied: "At present, the best method is still to carefully inspect the insulation tiles after each flight and replace the insulation tiles in time."

"Other than that, we haven't found any better solution yet. After all, we have adjusted and adapted the thermal barrier-related optimization designs on the traditional space shuttle and applied them to Xinghai. It will be very difficult to optimize it in the future. "

In terms of thermal insulation of space shuttles or spacecraft, the technologies currently used can be roughly divided into three types.

The first is endothermic heat protection. In some parts of the return cabin, metal endothermic materials with good thermal conductivity, high melting point and large heat capacity are used to absorb a large amount of aerodynamic heat; the second is radiant heat protection, which uses Composite materials such as alloys and ceramics with radiation properties radiate heat away.

The last one is ablation heat protection, which uses the method of melting, evaporating, sublimating or decomposing and vaporizing the surface part of the polymer material to take away a large amount of heat when the polymer material is heated at high temperature.

These technologies can basically be integrated into external materials such as insulation tiles and insulation cotton.

In fact, as materials science continues to develop today, their, or rather China's, achievements in insulation materials for the exterior of spacecrafts have surpassed that of the United States today.

But at least, there is no problem in surpassing the insulation tiles used by the American space shuttle.

However this doesn't solve the problem.

Under the high temperature corrosion of more than 1,000 degrees to nearly 2,000 degrees, no matter how powerful the performance of the insulation material is, at least based on the current material level, it cannot guarantee 100% safety performance.

Xu Chuan nodded and tapped his fingers lightly on the desk: "Okay, I understand. I will organize a meeting to discuss this matter. Are there any other questions?"

For now, overall, the method Weng Yunzong said is indeed the best and most appropriate method at present.

The thermal insulation materials used on the Xinghai are already the best and most excellent materials developed by China.

To solve this problem, we need to find a way in the future.

Of course, the urgency of this issue is not that exaggerated. In subsequent aerospace activities, doing a good job in testing is also a means of coping.

Moreover, a flight life of 10-12 times is currently long enough for a space shuttle.

Weng Yunzong nodded and said: "We have corresponding optimization solutions for some other problems. In comparison, these two are more critical."

"Well, okay." After a reply, Xu Chuan continued: "You must strictly control the relevant specific work. Any problem on the space shuttle is a big problem and cannot be easily ignored."

"Well, I'll keep an eye on this."

After discussing the data on the Xinghai's maiden voyage and some of the problems exposed for a while, Xu Chuan asked: "When will the maintenance inspection of the Xinghai be completed?"

Weng Yunzong thought for a while and replied: "The first flight inspection will be more careful, and it will probably take about ten days."

When it comes to Xinghai's flight inspection and maintenance, it cannot be systemized in detail.

In order to conduct a detailed inspection of the overall condition of the Xinghai after its first voyage, engineers and technicians at the space base, with the support of established aerospace groups such as Aerospace Science and Technology and Aerospace Science and Industry, almost dismantled the entire space shuttle into eight pieces.

Although it has not been dismantled into individual parts, the equipment with each system as the core, such as small controllable nuclear fusion reactors, aerospace engines, air compressors, etc., have all been modularly disassembled.

Then, these parts were quickly tested by the relevant working groups and the original manufacturers to verify whether there were any problems with these parts during the first voyage.

It can be said that it was just a matter of dismantling it into pieces, inspecting the screws one by one, and then reassembling it.

Of course, this level of inspection and maintenance can also ensure the safety of the Xinghai to the greatest extent.

Their time is very tight, and they will probably only conduct a few more unmanned flights + manned spaceflight low-Earth orbit tests in the future. If Xinghai performs perfectly in these few flight experiments, manned landings will almost be launched. It’s been months.

There is no way, the last flight of Xinghai greatly stimulated the nerves of the United States and NASA.

It was originally expected that NASA would start its manned lunar landing project in the second half of this year. But now, there is accurate intelligence news that NASA has accelerated the pace of the Artemis program and will officially launch it in two months. Send a manned spacecraft to the moon and return to the moon.

Two months is a pretty tight area for them.

Xinghai has completed its maiden voyage. After continuous testing and inspection work, it is not impossible to complete a manned moon landing.

But overall, compared to the expected plan, the time is still quite tight.

After all, manned space activities are a very cutting-edge work. Only the United States and the United States have the ability to independently complete manned space activities and launch manned spacecraft independently, even if it is just to send people to low-Earth orbit. Three countries: Tsarist Russia and China.

As for manned landing on the moon, only the United States has done so.

For China, although it has a record of landing on the moon, it has sent the Chang'e probe to the moon three times. But it is undeniable that there is no experience in manned moon landing.

And these all require ample time to prepare.

After sending Weng Yunzong away, Xu Chuan picked up the data analysis report on the table and started reading it again.

If the Aerospace Research Institute can complete the wing design and space shuttle stability work on its own, then the current Xinghai Research Institute, or even the entire aerospace group, may not be able to find enough optimization for the thermal barrier effect generated when the Xinghai returns. or solution.

After all, if he can find it, Weng Yunzong will definitely report it.

Of course, this does not mean that they are not strong enough in the aerospace field. But this thermal barrier problem has not yet been solved all over the world.

Even the United States, known as the largest aerospace power, has not been able to solve this problem. The difficulty can be imagined.

Although judging from the current situation, this is not an imminent trouble that needs to be solved immediately, its potential dangers cannot be ignored.

At least, for Xu Chuan, it is still necessary to find a solution to this problem.

The days passed like this day by day, in the Xinghai Research Institute/Space Base.

After optimizing and solving the minor troubles that could be accomplished during the first flight, Xinghai conducted unmanned flight experiments several times. Each time was quite successful, and it also accumulated valuable information for China's aerospace field. quite a wealth of experience and data.

Xu Chuan did not personally lead the subsequent flight experiments after the maiden flight, and handed them over to Weng Yunzong of the Aerospace Research Institute.

He has always believed that the progress of a country, a race, and a civilization cannot be supported by the strength of one person. This is also the reason why he has always maintained his professorship at NTU, and whenever he has time, he will basically go there to give classes and mentor students.

The same is true in the fields of controllable nuclear fusion and aerospace. After the relevant major issues are resolved, he leaves the subsequent development to other personnel to cultivate their talents in these fields.

Today is the last unmanned flight. After the final tests and experiments, a deep space acceleration test will be carried out in the vast outer space to verify the relevant simulation data.

Following the command of 'set sail', the red-purple tail flame was dragged towards the sea of ​​​​stars again.

Compared with the test of the first flight, this time Xinghai will almost go straight to outer space, and the flight time will be much shorter, but even so, it will still need enough time to climb the gravity well.

This is the shortcoming of the electric propulsion system. Compared with the explosive power of traditional chemical fuel propulsion, it is more suitable for long-term endurance.

In the control center, after Xu Chuan watched the Xinghai go away, he looked at Academician Chang Huaxiang sitting next to him and said:

"If this voyage goes well, the next one will be manned space flight, right?"

Although he was invited to serve as technical director, there is no doubt that in the field of aerospace, Academician Chang has more experience than Xinghai Research Institute/Aerospace Research Institute.

Even the old aerospace groups in the later period also arranged corresponding expert groups to enter the aerospace base to guide the work, but all arrangements in the aerospace field are still led by this big boss.

As for himself, experts in the non-aerospace field have basically not been involved in aerospace-related work except for some technical problems.

Chang Huaxiang nodded and said: "Compared with traditional spacecraft, which require many unmanned space experiments before they can land humans, the space shuttle, especially the Xinghai we designed and manufactured, has great advantages in this regard. Advantage."

“Its long-term endurance brings the ability to cope with various environments and work situations, so it is safer and more adaptable.”

Xu Chuan nodded and said, "How is the training for the astronauts?"

Manned spaceflight naturally requires astronauts.

Compared with traditional chemical fuel launch vehicles, the Xinghai space shuttle does not have high physical requirements for astronauts.

Even judging from the test data of several flights so far, the acceleration is completely bearable even for an ordinary person without training.

However, as this is the first manned flight, the personnel arrangement will naturally be experienced active astronauts.

Xu Chuan didn't worry about this matter, and the senior management directly dispatched astronauts and related personnel.

The candidates for this manned space flight of Xinghai were led by Comrade Zhai*gang, who had completed many manned spaceflights before and was the first person to walk in space in China, and selected two top-notch personnel from the Air Force. The pilot acted as an assistant throughout the entire process.

At present, these three people have been in the space base for several months, and have been continuously conducting relevant training work.

Hearing Xu Chuan's question, Academician Chang Huaxiang, who knew everything, replied without hesitation: "There is no problem with the astronauts. Under the leadership of Comrade Zhai Gang, the training work went smoothly and they are ready."

Xu Chuan nodded and fell into thought.

To be honest, he really wanted to go up and have a look.

After all, the universe and the sea of ​​stars are every man’s dream. Especially for a physicist like him, it has a fatal attraction.

However, as far as the current situation is concerned, it is impossible for anyone to allow him to go up with these astronauts during the first manned flight.

For this kind of thing, if you apply to the higher authorities, there is more than a 99% chance that you will not be able to apply.

"Would you like to sneak up and have a look?"

Thoughts flashed through his mind, and Xu Chuan fell into entanglement and hesitation.

Perhaps this is the only way he can go to space in a short time, but to be honest, it is a bit too risky, at least for the first manned space flight, it is a bit risky.

Although there have been several unmanned flights before, and the Xinghai's performance was perfect, it is still unknown what the situation will be like after people get on board. After all, this is the first time.

After hesitating for a long time, Xu Chuan finally shook his head and suppressed the thoughts in his mind.

Now is not the time for him to take risks. After all, he has been reborn. He still has many dreams that have not been realized, and the road is still far from the end.

Not to mention the more distant future, the physical future of dark matter, dark energy, and gravitons is still waiting for him.

Not only that, the mathematics he has learned in this life is enough to take him further in the field of physics, and even research in the field of mathematics. He also has the possibility of going further.

Perhaps it would be more appropriate to wait until his road comes to an end again in the future to do something he wants to do.