The military-industrial scientific research system of the academic master.

Chapter 1279 Goal: Breakthrough Near Space

At the same time, China.

Due to the particularity of the space fishing boat program, the Second Artillery Corps responsible for the launch mission itself had already withdrawn from Qiong Province long after confirming that the satellite had successfully entered orbit.

Only technical personnel like Chang Haonan and administrative staff in charge of logistics were left to follow up on the situation.

Of course, now that everything is over, there is nothing for them to follow up on.

In fact, according to the original plan, the front-line personnel should have withdrawn from Qiong Province to the capital in batches as early as last night.

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

Zhou Pingjian also stayed with them on the grounds of "investigating the site selection for a low-latitude rocket launch site."

"That's right, Old Zhou."

As the group was on their way to the launch site, Chang Haonan suddenly asked:

"I told you to sort out the expenses of the entire project..."

Before he finished asking, Zhou Pingjian quickly replied:

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

Chang Haonan nodded:

"Has the R&D funding for Kuaizhou-1 and the costs of the two previous ground tests been included?"

"We directly list the costs of each link in the launch mission, and then change the symbol in front of the amount from RMB to US dollars before publishing it."

Zhou Pingjian chuckled:

"If we do a simple calculation, it covers not only the R&D costs of Kuaizhou-1 and modular satellites, but also the costs of Shenzhou-7 and Tiangong-1..."

Chang Haonan thought to himself that you guys are more cruel.

During the arms sales process, the CNY symbol was directly replaced with the USD symbol. He had always thought of this as a joke.

I didn't expect that I would be so rushed now.

And guess what?

NASA has us to thank!

"Speaking of which, Academician Chang."

After a while, Zhou Pingjian looked at the launch site that was already vaguely visible in the distance, and suddenly he became curious:

“Although this launch site in Qiong Province has the word ‘rocket’ in its name, the largest objects launched in the past 331 years were the Peace 2 with a takeoff weight of 285kg and the Vega with a takeoff weight of kg. At most, it can send a probe weighing ten kilograms to an altitude of about kilometers. It can’t even be considered a suborbital launch…”

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

Chang Haonan answered almost without thinking:

"Because my next step is to study rarefied gas dynamics..."

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

He was stunned for a while before he finally reacted:

"Theoretical research?"

"Well... not exactly."

Chang Haonan organized his words:

"Ultimately, it's for the hypersonic weapons project later on, but if we can solve some theoretical problems related to rarefied gases in the process, it will also be helpful for the hypersonic aircraft itself."

Zhou Pingjian looked a little puzzled:

"But I heard that the Institute of Mechanics in Miyun has already built a JF14 super-high-speed wind tunnel?"

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

"Initially, I was planning to complete all preliminary verification tests in the JF14 wind tunnel. However, during the time I was in charge of the space fishing boat project, I had many discussions with colleagues from CASIC and found that the flight conditions in near-space at an altitude of 50-150km were much more complicated than expected."

"The current JF14 wind tunnel can only reproduce high speeds and high total temperatures. This is sufficient for studying hypersonic aircraft that generally operate at altitudes below 40km in the atmosphere, but for trans-atmospheric aircraft that fly at higher altitudes, many key theoretical elements are still lacking..."

He said this very calmly, but to Zhou Pingjian on the other side, it sounded like a thunderclap:

"Trans-trans-atmospheric vehicle?"

This somewhat startled reaction made Chang Haonan stunned, and then he realized that the other party might be overthinking it.

"I don't mean aerospace vehicles... at least not yet."

He quickly explained:

"From a classification perspective, any vehicle that can operate at near-space altitudes for a relatively long time, including fully gliding hypersonic vehicles that use rocket boost as initial propulsion, and even space shuttles, can be considered a type of trans-atmospheric vehicle."

Hearing this, Zhou Pingjian finally breathed a sigh of relief.

It seems that in the short term, the function of the traditional rocket + spacecraft combination is still the only one, and it will not be suddenly replaced by something that the amazing Academician Chang in front of him has tinkered with.

Read the error-free version at 69shuba! 6=9+shu_ba is the first to publish this novel.

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

When China first planned its manned space program, someone proposed a more complex space shuttle plan that would have greater carrying capacity and mission flexibility.

The reason why it was later rejected by Mr. Qian was not only because the cost was indeed outrageous, but also because 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 planning to use this place as a research base to conduct a series of scaled-down near-space flight experiments?"

“This is the initial idea.”

Chang Haonan replied:

"You should know that Qian had already proposed in 1946 that the optimal flight altitude for 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 rarefied environment of near-space, the mean free path of the molecules in the flow from a hypersonic vehicle increases significantly. For the macroscopic reference scale for studying the overall aerodynamic characteristics of the vehicle, the flow around the vehicle already meets the standards of transitional flow. Therefore, the surface velocity slip, temperature jump, and the formation of the Knudsen layer make the traditional continuous flow calculation method completely inaccurate in predicting the aerodynamic characteristics of the vehicle..."

It is almost impossible that aerospace personnel of Zhou Pingjian's generation 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 around aircraft are basically multi-scale flow systems, and often have local rarefaction effects. They cannot be simply defined as completely continuous flow or transitional flow?"

It was indeed beyond Chang Haonan's expectation that the other party could remember the key points so quickly.

"That's right...so I plan to go a step further based on what Mr. Qian has done."

He answered solemnly.

Zhou Pingjian looked shocked, he just opened his mouth but didn't say anything.

After a brief silence, Chang Haonan continued:

"When the Knudsen number approaches 0, the gas can be directly assumed to be a continuous medium, and the NS equation can be directly used to solve it just like in the atmosphere. If the Knudsen number is greater than 10, the collisions between molecules can be ignored, and only the collisions between molecules and surfaces need to be considered, which are relatively easy 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!"