my scientific age

Chapter 257 Can a 75mm cannon be designed?
Again, what suits you is the best.

The three-stage centrifugal compressor is good, but the basic industrial level is very weak, and it does not have the processing and manufacturing conditions at all.

Yu Hua preliminarily determined the design of the air intake unit of the compressor composed of the two-stage centrifugal compressor and the turbine, and then set various values ​​such as the working power and size of the compressor according to the air intake value of the air intake unit.

The working power of the compressor is determined by the motor, and the motor power needs to meet the standard of handling 1014 cubic meters of air per hour.

Yu Hua's face was calm, and his mind was running at high speed to quickly calculate the specific motor power parameters, and then determine the type and size of the motor according to the power parameters.

Technology research and development is like this. One parameter determines another parameter. It must be progressive. Any problems in any step will lead to failure.

Soon, Yu Hua determined the motor rated power and maximum power of the compressor and other related parameters, and turned his attention to the most important compression structure of the compressor.

The compression structure directly affects the air compression performance of the compressor.

"Traditional piston compressors can't handle 1014 cubic meters of air intake per hour. It's fine for cars and propeller planes, but it's a drop in the bucket for air separation plants. I can't make an oversized cylinder and piston. At that time, the difficulty of materials and processing technology will skyrocket again... It's a bit troublesome, I only had a simple understanding of the information on air separation equipment, but I didn't expect this thing to be so complicated." Yu Hua turned the pencil in his right hand, and his eyes showed thought. Color, the mind constantly rummages through the memory, and vertically searches for technical information about the air separation equipment in the brain memory information like a database.

When I was learning the oxygen top-blown converter technology at Station B, the video I watched mainly focused on metallurgical engineering and machinery, and I just skipped over the air separation plant.

A bit of a headache.

Yu Hua can't find a compression structure that can efficiently handle the huge amount of air.

The large-scale application of the piston compression structure of tank engines and aircraft engines simply cannot handle so much air.

This is not dozens or hundreds of cubic meters of air per hour,
how?
Yu Hua pondered for a while, but couldn't find any relevant reference materials. His brows were slightly wrinkled, and he was a little unexpected about this situation.

Yu Hua had expected the technical research and development difficulty of industrial-grade air separation equipment. However, he did not expect it to be so difficult. The research and development difficulty far exceeded psychological expectations.

Now, the progress is stuck here in the compressed structure.

The key is that the compression structure is extremely important, and Yu Hua cannot avoid it, let alone solve it by tricks.

If the problem of the compression structure is not solved, the air separation plant will not be able to come out. If there is no air separation plant, the so-called oxygen top blowing converter is a joke.

"No hurry, take your time, no reference material means nothing." Yu Hua was not flustered in this situation, his breathing was steady, his face was calm, and he thought for a while. Fortunately, he packed up all the drawings, packaged them, and then went on to Get up and go downstairs to the mechanical hall.

There are no references, but he can request tactical support.

As the Tsinghua Garden, the highest university in China, there are world-class top mechanical engineering experts and aviation power experts. Yes, this person is still Professor Zhuang.

Yu Hua doesn't have the stinky problem of pretending to understand and insisting, and he has to ask when he needs to ask.

He walked quickly to the Machinery Museum. After checking his identity, Yu Hua stepped into the museum. As soon as he arrived at the door of the Mechanical Engineering Laboratory, a series of shrill voices came from inside. Professor Zhuang, who is the head of the Department of Mechanical Engineering at Tsinghua University. , did not stay in the office drinking tea, but soaked in the laboratory to learn.

The knowledge that is exclusive to the field of mechanics.

It was the gantry milling machine that made the sound. There was a square steel plate on the worktable with a thickness of about 5 mm and an area of ​​30 cm x 25 cm, which was slightly larger than a textbook. Point the hole, and there are also several pieces of square steel plates that have been processed.

Yu Hua stood quietly, not disturbing Professor Zhuang who was at work.

After a while, the working sound of the gantry milling machine is weakened and the milling head rises, leaving a steel plate with a smooth surface and four corners.

"How's the final exam result?" Professor Zhuang, wearing protective gloves, took off the slightly warmer square steel plate, checked it carefully and confirmed that it was correct, looked at Yu Hua, and asked with a smile.

"Students who are recommended to enter the school do not need to take the final exam of this semester." Yu Hua heard the words, saluted, and saluted as a student. His words were respectful and natural, and he replied with a smile.

Zhuang Qianding was stunned for a moment, and then he recalled Yu Hua's identity as a escort student. He smiled and shook his head: "I forgot that you were a escort, look at my brain."

"Professor, what are you processing?" Yu Hua's eyes revealed a hint of curiosity. Looking at the square steel plate in Zhuang Qianding's hand, he couldn't figure out its purpose.

"I was bored and I remembered the bulletproof vest I saw in the U.S. Army before. I made a bulletproof vest design myself. I call it a bulletproof vest."

Zhuang Qianding put the processed steel plate on the ground and sighed: "It happens that there are some scraps left in the laboratory, so I am going to build a few sets. The performance of these imported steel from the United States is very good, and the thickness of 5 mm can withstand a distance of 200 meters. The 6.5mm Arisaka bullet shooting, as well as the fragmentation of artillery shells and grenades, can greatly improve the survival rate of soldiers on the battlefield.

"Bulletproof vest?" Yu Hua was a little surprised when Professor Zhuang's voice echoed in his ears when he heard this very modern term.

I haven't seen you for a few days. Professor Zhuang, you have crossed from the vertical deep hole drilling machine to the field of body armor, really...

Yu Hua can only say that he is awesome.

As for the body armor itself, Yu Hua is not very surprised. The concept of body armor comes from ancient armor. It was first born during the First World War and was made of ordinary steel. However, due to the strength of the material, the bulletproof performance is not high.

Around the 20s, the United States developed scale-like steel bulletproof vests. Compared with earlier bulletproof vests, the bulletproof performance has been greatly improved, but it still cannot defend against direct rifle bullets, and can only defend against pistol bullets, grenade fragments and shell fragments. .

Of course, bulletproof vests are not popular, and only used by a very small number of troops, which can be called military luxury.

With an MS in Mechanical Engineering from Cornell University and a MS in Chemical Engineering from MIT, Professor Zhuang is not surprised to learn about body armor.

Yu Hua took the design drawing with some oil stains in his right hand and looked carefully. The bulletproof vest on the drawing is composed of a jacket and a protective layer. Similar to modern bulletproof vests, it mainly protects the torso, not the limbs and head. Made of steel plates.

Simple, rude.

After a while, Zhuang Qianding smiled and asked, "How is it?"

"Professor, there is no problem with the concept, I think some small improvements can be made to the bulletproof layer." Yu Hua said after pondering.

"Tell me." Zhuang Qianding nodded.

"I suggest that the bulletproof layer can refer to the composite armor that the British once used on warships, add a layer of ceramic plate and a layer of cement iron wire, the thickness of both is controlled within 5 mm, the outermost layer is cement iron wire, and the middle layer It is a ceramic plate, and the innermost layer is a 5mm steel plate. In this case, according to calculations, the protection should be improved to 50m-100m with 6.5mm Arisaka bullets and 350m-550m with 7.92mm heavy-pointed bullets." Yu Hua gave Make your own suggestions.

The bulletproof vest developed by Professor Zhuang has been perfected in concept, and there is no need for improvement. The bulletproof layer can be read here.

Yu Hua did not propose any unrealistic protective materials such as Kevlar, nylon, FRP and UHMWPE fibers.

As for the liquid body armor of non-Newtonian materials, don't even think about it.

The simple and crude cement barbed wire and ceramic pieces are very solid.

The materials are extensive, the cost is cheap, and the disadvantage is just one word - heavy.

But this flaw is extremely trivial in the face of death.

To be fair, Professor Zhuang woke up Yu Hua. He had fallen into a weapon and only thought of firearms, completely forgetting the existence of defensive military equipment.

What technical content is required for the bulletproof vest composed of cement iron wire board, ceramic board and [-]mm steel plate?

Sorry, this thing has almost zero technical content.

When Zhuang Qianding got Yu Hua's answer, he was a little surprised, fell into deep thought, and asked: "I didn't expect that you still have research on weapons, and the protection power has improved so much. Is it because of the kinetic energy attenuation and interference caused by bullets penetrating materials of different densities? ?"

Zhuang Qianding didn't doubt Yu Hua's bragging, because he knew very well about Yu Hua's computing power. What he was surprised about was that just adding two layers of bulletproof layers could increase the protection from 200m/6.5 Arisaka bullets to 50m-100m. m/6.5mm Arisaka bullet.

In addition, it can defend against the shooting of 350mm heavy-pointed bullets at about 7.92 meters.

7.92mm heavy-pointed bullet, which is the bullet used by the domestic army machine gun, in other words, the protection has reached the level of protection against machine gun bullets.

Although it is 350 meters, it is not much better than the previous protection.

"Yes, the current bullet design is based on the balance of the Danone effect, the penetration force and the stopping force. After the bullet shoots substances of different densities, the kinetic energy is attenuated and is interfered by the reaction force from the material, plus the stopping force and the Danone effect. The penetration force of the bullet will drop rapidly in a short period of time. This is a mathematical model, which the students studied not long ago." Yu Hua nodded, picked up the paper and pen that Zhuang Qianding had placed next to him, and wrote out the theoretical model and mathematics. The calculation process, and the final data.

After Yu Hua wrote out the theoretical model and calculation process, Zhuang Qianding picked up the draft paper that had undergone rigorous mathematical calculations and reviewed it carefully.

Yu Hua stood next to him, watching Zhuang Qianding's expression slowly change from serious to solemn, and a faint sense of pleasure appeared in his heart. This kind of speech in the academic field and being valued by top professors is very important to a new recruit. As far as academics are concerned, it is really comfortable.

After a few minutes, Professor Zhuang slowly put down the scratch paper and looked at Yu Hua.

"I have to say, this is another research result, a research result that cannot be made public. Why didn't I find research results so easy to come out before? Yu Hua, how deep is your research on weapons?"

"Uh...what do you mean? Academically, students can accurately calculate the lethality and kinetic energy data of various types of bullets, calculate the parabola and landing point of the shell, and the maximum range, and calculate the performance values ​​of different rifles. In terms of application, Students can design a rifle, they can design a mortar, and so on.”

"Can you design a 75mm cannon?" Zhuang Qianding heard the words, and his eyes lit up. He didn't expect that Yu Hua's research in the field of weapons had reached this level, reaching the level he was at MIT.

Yes, he Zhuang Qianding is not only a mechanical expert, chemical expert, aviation power expert, but also a very professional weapons expert.

The reason is very simple, if you understand mechanics, you understand weapons, if you understand chemical engineering, you understand ammunition, and the dynamics are the same.

Although Zhuang Qianding has never participated in the research and development of any military weapons and equipment, his level is definitely top-notch.

"No." Yu Hua wanted to say yes, but after thinking about it, he was still not ready to tell the truth. It is very difficult for a student who has just entered Tsinghua University to understand this. If he still knows how to design a 75mm cannon, I'm sorry, Yu Hua is completely Can't explain.

Hey, wait, what am I doing here in the mechanical hall?

(End of this chapter)