The military-industrial scientific research system of the academic master

At the same time, China.

Due to the particularity of the space fishing boat plan, the Second Artillery Force responsible for the launch mission itself had already evacuated Qiong Province after it was confirmed that the satellite had been successfully put into orbit.

Only Chang Haonan and his technical staff, as well as the administrative staff responsible for logistics work, were left to continue to follow up on the situation.

Of course, it's all over now, so they have nothing to follow up on.

In fact, according to the original plan, as early as last night, the frontline personnel should have withdrawn from Qiong Province to the capital in batches.

However, Chang Haonan specifically asked to stay one more day to meet Liu Mengyuan, the person in charge of the sounding rocket launch site.

Zhou Pingjian also stayed with him on the grounds of "inspecting the location of a low-latitude rocket launch site."

"That's right, Lao Zhou."

On the way to the launch site by car, Chang Haonan suddenly asked:

"As I said before, I asked you to sort out the expenses of the entire project..."

Before he could finish asking, Zhou Pingjian quickly replied:

"Before setting off this morning, I called specifically to ask. They said that everything has been sorted out and should have been posted to the official website of the space agency by now..."

Chang Haonan nodded:

"Including the research and development funds for Kuaizhou-1 and the costs of the previous two ground tests, have they all been paid in?"

"We directly listed the costs of each link in the launch mission, and then announced the amount in front of the amount from RMB to US dollars."

Zhou Pingjian chuckled:

"If you do a simple calculation, not only the research and development funds for Kuaizhou-1 and modular satellites, but even the costs of the Shenzhou-7 and Tiangong-1 missions can be covered..."

Chang Haonan said in his heart that you are the more evil-hearted.

During the arms sales process, the CNY symbol was directly replaced by the USD symbol. He had always heard it as a joke.

I didn’t expect that I would really be in a hurry now.

And guess what?

NASA has to thank us!

"Speak of it, Academician Chang."

After a while, Zhou Pingjian looked at the launch site that was vaguely visible in the distance, and suddenly felt a little curious in his heart:

"Although this launch site in Qiong Province also has the word "rocket" in its name, in the past nearly thirty years, the largest things launched were the Peace 2 with a take-off weight of 331kg and the Weaver 3 with a take-off weight of 285kg. At most, ten Sending a kilogram-weight detector to a place about a hundred kilometers high is not even considered suborbital..."

"And even if the country builds a new space launch site in Qiong Province in the future, it will definitely choose a place close to the coastline where a large port can be built directly. Why do you suddenly think of inspecting the situation there?"

Chang Haonan answered almost without thinking:

"Because my next step is to study the dynamics of rarefied gases..."

This reason was obviously completely beyond Zhou Pingjian's expectations.

So much so that he was stunned for a while before finally reacting:

"Theoretical research?"

"Hmm... not entirely."

Chang Haonan organized the language:

"In the final analysis, it is for the subsequent hypersonic weapons project, but if some theoretical issues related to thin gas can be solved in this process, it will also be helpful to the hypersonic aircraft itself."

Zhou Pingjian looked a little puzzled:

"But I heard that a JF14 ultra-high-speed wind tunnel has already been built in Miyun, where the mechanics department is located?"

Chang Haonan lowered his head and thought for a moment, then shook his head gently:

"In the beginning, I was indeed planning to rely on the JF14 wind tunnel to complete all preliminary verification tests. However, during the period when I was responsible for the space fishing boat project, I communicated with comrades from the Aerospace Science and Industry many times and found that the altitude range is 50-150km. The flight situation in near space is much more complicated than expected.”

"The current JF14 wind tunnel can only restore high speeds and high total temperatures. It is sufficient for studying hypersonic aircraft that generally operate at altitudes below 40km in the atmosphere, but for transatmospheric aircraft that fly at higher altitudes, Many key theoretical elements are still missing..."

His words were said very calmly, but to the ears of Zhou Pingjian opposite, it was almost like a thunder:

"Trans...transatmospheric vehicle?"

Chang Haonan was stunned by this somewhat startled reaction, and soon realized that the other party might have been thinking too much.

"I'm not talking about amphibious vehicles... at least not yet."

He quickly explained:

"From a classification point of view, as long as they operate at near space altitudes for a relatively long time, including fully gliding hypersonic vehicles that use rocket boost as the initial power, and even space shuttles, they are all considered to be a type of transatmospheric vehicle."

After hearing this, Zhou Pingjian finally breathed a sigh of relief.

It seems that in a short period of time, the function of the traditional rocket + spaceship combination is still the only one, and it will not be suddenly replaced by something tinkered with by the magical Academician Chang in front of me.

The error-free version is being read! 6=9+Book_Bar debuts this novel.

In fact, for him, research related to near space is not completely unfamiliar.

When China first planned its manned spaceflight project, someone proposed a space shuttle plan that was more complex but also had greater carrying capacity and mission flexibility.

The reason why Qian Lao later rejected it was that, in addition to the outrageous cost, an important technical factor was that the space shuttle needed to operate at an altitude of 50-150km for a longer time than the spacecraft, and even needed to maintain a certain degree of maneuverability during the process. At that time, China, or the entire human race, had a very limited understanding of near-space.

"So Academician Chang, are you going to use this place as a research base to conduct a series of scaled-down near-space flight tests?"

"This is the initial idea."

Chang Haonan replied:

"You should know that as early as 1946, Qian had already proposed that the optimal flight altitude of long-range gliding aircraft is about 96 kilometers, and divided the flow into continuous flow, slip flow, transition flow and free molecular flow according to the Knudsen number."

"In the high-altitude and rarefied environment of near-space, the mean free path of the molecules of the hypersonic aircraft flow increases significantly. For the macroscopic reference scale of studying the overall aerodynamic characteristics of the aircraft, the flow around the aircraft has met the standards of the transition flow. Therefore, the surface velocity slip, temperature jump and the formation of the Knudsen layer make the traditional continuous flow calculation method completely inaccurate for predicting the aerodynamic characteristics of the aircraft..."

It is almost impossible for a generation of aerospace personnel like Zhou Pingjian to have not read Mr. Qian Xuesen's monographs and papers.

Although it has been a long time, the latter can still recall many details:

"But I remember... the Knudsen number proposed by Mr. Qian is just a conceptual qualitative division. Near-space slip and transitional flow aircraft flow systems basically have multi-scale flow characteristics, often with local rarefaction effects, and cannot be simply defined as completely continuous flow or transitional flow?"

The other party was able to remember the key points so quickly, which was indeed somewhat beyond Chang Haonan's expectations.

"That's right... So I plan to go a step further on the basis of Mr. Qian."

He answered solemnly.

Zhou Pingjian was shocked, but he just opened his mouth but didn't speak.

After a short silence, Chang Haonan continued:

"When the Knudsen number approaches 0, the gas can be directly assumed to be a continuous medium, and the N-S equation can be directly used to solve it just like in the atmosphere. If the Knudsen number is greater than 10, the collision between molecules can be ignored, and only the collision between molecules and surfaces needs to be considered, which is a relatively easy part to solve..."

"But when the Knudsen number is in the range of 0.01 to 10, the problem can only be solved by numerically or analytically solving the Boltzmann equation..."

"And... this is also the most unified way to solve the problem of rarefied gas flow!"