The rise of nanometers

In Jiuquan in June, under the bright sun, it is the best months of the year for light and heat conditions. Farmers are busy planting crops.

A convoy moved northwest in a low-key manner. Jiuquan Satellite City was not in Jiuquan, but came to Jinta County in Jiuquan. It is responsible for 95% of the infrastructure of Jiuquan Satellite City, while at the launch site of Alxa League, it only accounts for the total infrastructure. about 5%.

Nie Guanghua, the person in charge of the base, as well as academicians Zhang Peicai and Wang Kan, who have been busy here for some time, and Li Feng from Harbin Institute of Technology, all appeared at the door to welcome Huang Xiuyuan's arrival.

Get off the bus.

Huang Xiuyuan smiled and said hello: "Academician Zhang, Academician Wang, long time no see."

"Haha, you did a good job." Zhang Peicai came up and patted him on the shoulder.

Wang Kan, who was standing next to him, was white-haired but in good spirits. He smiled as he walked and said, "I invite you here this time mainly for a few things. There will be a launch mission in a few days, which is to send a satellite into space."

Huang Xiuyuan thought about it in his mind and knew that this satellite was the Shijian No. 12 satellite. He asked thoughtfully: "You are talking about this specifically. It seems that the launch vehicle of this satellite uses a fixed Sent?"

"It is indeed a fixed-launch vehicle. We originally planned to use a long-term launch vehicle, but our fixed-launch research and development already has several small-load versions. After discussing with a few old guys from the aerospace industry, I decided to switch to a fixed-launch vehicle. Launch vehicle." Zhang Peicai explained.

Small payload version? I’m afraid it’s not directly modified from Dongfeng, right? Huang Xiuyuan understood instantly.

The previous secret tests at the Qinling base were directly adapted from Dongfeng's old models. After all, it would take at least three years to redesign a solid-fuel launch vehicle.

According to the scientific research funding of the domestic aerospace industry, we can only pursue cost-effectiveness instead of bells and whistles. Renovating it with the old Dongfeng is currently the most suitable choice.

After walking, we came to the general assembly workshop.

Many young researchers, technicians and engineers are doing final inspections around a launch vehicle.

"Chang 11?" Huang Xiuyuan saw a line of letters and numbers printed on the coating of the launch vehicle: CZ-11-A

"It's just a code name." Wang Kan had a sly look in his eyes.

Huang Xiuyuan took the document handed over by Zhang Peicai, which contained some parameters with a length of 11. After flipping through it for a few minutes, he found that the overall performance of this launch vehicle was good.

The overall take-off mass is 287 tons, the low-Earth orbit payload reaches 14.92 tons, and the payload ratio is 0.052, which is about 5.2%.

We must know that the payload ratio of Chang 2 is only about 0.012, and the overall mass reaches 458 tons, of which the proportion of payload is only about 5.5 tons.

As for the famous Fat Five, with an overall weight of about 800 tons, the payload in low-Earth orbit is only about 25 tons, with a payload ratio of 0.031; in geosynchronous orbit, it is about 12 tons, with a payload ratio of 0.015.

"Hello! Mr. Huang, nice to meet you."

Huang Xiuyuan, who was concentrating on reading the information, was awakened by a voice. When he looked up, he saw a middle-aged man with a Chinese character face. He recognized the other person's identity immediately.

"Hello, Mr. Zhang."

Zhang Mingliu is an engineer at the Modu Aerospace Technology Research Institute and the chief engineer and project leader of the Shijian-12 satellite.

Academician Wang Kan on the side looked at the worried Zhang Mingliu and comforted him in a low voice: "Mingliu, don't worry. Chang 11 has been tested several times and we have made an emergency plan. There will be no problems."

But Zhang Mingliu still had trouble calming down. After all, it was the first launch mission of the Chang 11 carrier rocket, and no one was sure.

Seeing this, Huang Xiuyuan changed the subject: "General Manager Zhang, I heard that you plan to cooperate with our company?"

When he heard about the cooperation, Zhang Mingliu immediately became interested: "Yes, our satellites can use things like solar panels and thermoelectric power generation, as well as your company's chips. We can consider cooperation."

Several people also discussed it.

New solar panels work in outer space to achieve maximum efficiency because there is no atmosphere to weaken them.

Also in terms of thermoelectric materials, they can be used to quickly dissipate heat from components inside satellites and to generate electricity from isotope nuclear batteries.

After discussing for a long time, Zhang Mingliu talked about this launch mission again.

"Academician Wang, I'm still not sure. This launch mission involves another piece of equipment." At this point, Zhang Mingliu became speechless and depressed.

"Haha..." Academician Zhang Peicai felt a little embarrassed.

The reason why Zhang Mingliu is full of resentment is mainly because in this launch mission, the Chang 11 carrier rocket had two "passengers".

One is the Practice 12 satellite, and the other passenger is the Sentinel 1 experimental satellite.

This Sentinel 1 experimental satellite is actually a test version of the Queqiao relay satellite. Since the synchronous orbit load of Chang 11 reaches about 7.5 tons, the Shijian 12 satellite only uses about one-third of the payload, and the remaining payload is , the space agency intends to make full use of it.

Hence the emergence of the Sentinel 1 experimental satellite.

After hearing this, Huang Xiuyuan also looked confused and helpless. The older generation of scientists often pursue practicality and cost-effectiveness when doing things.

In their view, Chang 11 also has a synchronous orbit payload of about 5 tons. If it is not fully utilized, it will be a waste.

After looking through relevant information, he found that the design of the Sentinel 1 experimental satellite was also very simple and crude.

Since there is too much surplus payload, Academician Zhang Peicai's plan is to turn the payload into a core level two.

In other words, the rocket body of the Chang 11 launch vehicle is composed of three parts: the core first stage - solid fuel, the core second stage - liquid fuel + Sentinel 1 experimental satellite, and the core third stage - Practice 12 satellite.

Since the specific impulse of N20 solid fuel is as high as about 860, basically the power of the first stage is enough to send the 7.5-ton second and third stages of the core to the predetermined orbit.

If everything goes well, there will be about 10 to 15% of the fuel left, enough for the core stage to use the remaining fuel to forcefully return to the Blue Star's atmosphere.

Even Huang Xiuyuan, who agreed with the idea of ​​cost-effective development, couldn't help but remind him: "Academician Zhang, Academician Wang, are there too many projects in this launch mission?"

"Don't worry, we can still sort out priorities." Academician Wang Kan was full of confidence.

Academician Zhang Peicai explained: "The core level is enough to ensure that Practice 12 is in place. As for the recycling tests of Sentinel 1 and core level, even if they are unsuccessful, we will not lose much."

"Okay." Huang Xiuyuan has no choice. After all, the launch vehicle has been assembled and the launch time has been announced. Unless there is force majeure, the launch mission will not be canceled.

Huang Xiuyuan didn't care too much about this launch mission. He came here just in time for the meeting.

The main purpose of his invitation was actually for another matter.

Due to the rapid development of science and technology in the Suiren Department recently, especially in materials science, it has raised the level of China's materials field to a large level.

The aerospace field has very high requirements for materials. The new projects of Academician Zhang Peicai and others have encountered many problems, so Huang Xiuyuan was specially invited to come over, hoping to give some solutions or ideas.

After walking out of the general assembly workshop of the Chang-11 launch vehicle, under the leadership of Zhang Peicai, a group of people came to another assembly workshop next door.

There is also a launch vehicle on display here, but its size is slightly larger than that of Long 11.

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