The automobile industry is a comprehensive assembly industry, a car is composed of thousands of parts, components, each automobile OEM has a large number of related parts factories, so the automobile industry and many industrial sectors have close contacts.

The automotive industry is also a highly technology-intensive industry, with new materials, new equipment, new processes and new technologies in many scientific fields!

Therefore, the automobile industry is known as the industrial pearl.

It is no exaggeration to say that a country can make excellent cars, and it can make most of the conventional equipment and weapons used in modern warfare.

This, in the Second World War, was perfectly confirmed. Whether it's airplanes, tanks, rockets and missiles, or warships and submarines, automakers have done it all.

If you don't talk about it, let's talk about Japan.

Because of its strong maritime military strength during the war, Japan's shipbuilding industry was completely shut down by the United States after World War II. Almost all shipyards that can manufacture more than 5,000 tons were GG during the US occupation.

But after a decade of shipbuilding gaps, Japan can still build large warships, aircraft carriers, and submarines with the help of companies such as Mitsubishi and Kawasaki.

Like Hinata, Ise, and Atago, all of them are from the hands of automobile manufacturers.

The reason for this is that in many cases, the technology that is present in a small car can be replicated in other similar fields.

Zhengxin is the first car company in the country to have a large-scale experimental base covering vehicle technology, in the year of the establishment of Zhengxin company, Zhengxin's R&D center, it has set up a laboratory specifically responsible for noise suppression of the whole vehicle, that is, Zhengxin NVH laboratory.

This lab is more than just a unit. Instead, it includes a number of acoustic laboratories such as vehicle semi-anechoic chamber, powertrain semi-anechoic chamber, structural modal laboratory, and component absorption and insulation laboratory. It is a laboratory cluster that is capable of developing system services from vehicles to parts, from testing to CAE, and then to NVH performance, and has systematic product optimization and engineering verification.

So what does this lab do?

It's just to make a car with the best sound insulation effect and a quieter one. In the past few years, through a large number of automotive research and development, the laboratory has accumulated a large number of noise suppression technologies from a few screws, to the engine, to the whole vehicle.

These technologies, combined with Li Fanyu's design ability, will be applied to submarines, naturally!

"Director Xing, this is no problem!" Li Fanyu patted his chest on the spot.

cut

Isn't it just a submarine!

The automotive industry is too comprehensive, so it is a fine door.

In Li Fanyu's eyes, the submarine is nothing more than a larger car that does not run on the ground.

He thought so.

But when he really arrived at the place, saw the huge submarine hull in the dock that fluctuated slightly with the sea water, and felt the murderous aura and shock emitted by this modern weapon, Li Fanyu felt it......

Ahem, myself, I seem to think a little simpler......

Seeing Li Fanyu's shocked face, Xing Yaxin smiled slightly: "Dong Li, what's wrong?"

"Ahem," Li Fanyu hurriedly came back to his senses, "Eh, is what I said before too full?"

Xing Yaxin shook his head and smiled, and said with relief: "Do you know Dong Li, I graduated from the Naval Submarine Academy, and when I saw the real body of the submarine for the first time, my expression was the same as yours. At that time, when I was still a student soldier, I thought, how long the fuck will it take to develop and design and then produce and manufacture this thing. But it's easy to know that it's hard to do, as long as you start to do everything, you have the opportunity to do it well. This is the belief that has supported me, and even our comrades in the entire submarine research and development institute, to persist for so many years under the weak accumulation of technology and no channels to learn from!"

The expression on Li Fanyu's face gradually changed from sneering to resolute, and he nodded heavily, "I understand Director Xing!"

"Then let's ......" Xing Yaxin pointed to the Han-class nuclear submarine in the dock whose shell was seriously damaged and was undergoing overhaul.

"Let's start!" Li Fanyu smiled and waved his hand to the dumbfounded boys behind him, "It's time for us to play!"

……

920524 requirements are actually quite simple - to do everything possible to keep the underwater noise of the submarine to a minimum!

But achieving this goal is quite complex and not easy.

Xing Yaxin's proposal is to completely replace the current power system, completely abandon the current power take-off motor used on submarines, and replace it with Zhengxin's permanent magnet motor technology.

However, after conducting a practical investigation, Li Fanyu believes that a motor alone cannot solve the current problem of underwater noise in submarines.

It is true that the drive motors used in these submarines of the South China Sea Fleet are quite noisy. However, after he used his design expertise to inspect the entire power system of the three submarines, he found that there was considerable room for optimization in the design, regardless of whether it was a Han-class nuclear-powered submarine or the two Kilo-class diesel-electric conventional submarines.

The Han-class nuclear submarine mainly uses a nuclear reactor to directly drive the gas turbine, and the two Kilo-class submarines are large diesel engines to drive AC motors, from the transmission system, to the power supply system, and then to the power output terminal, the whole system is simply a large mechanical "band".

In addition, there are many loopholes in the layout of the power system. On his first inspection, Li Fanyu found a number of places that could directly transmit the noise of the transmission system to the hull of the submarine and resonate with the seawater.

But if that's really it, that's fine. With the current processing strength of Zhengxin Industrial Base, it is completely possible to manufacture more precise parts with smaller tolerances according to the current submarine design structure. The perfect coordination of the machinery is used to partially solve the noise source.

But the problem is that there are too many such parts involved in the entire submarine, and if this method of "refining" and "noise" is really used, then it is almost equivalent to remanufacturing half of the submarine!

Such an approach is obviously too costly. The effect achieved is also not proportional to the investment.

"Brother Fan, that's all for now. What do you think?"

After three days of structural investigation, the Zhengxin Power team summarized all the problems found so far. Looking at the dazzling array of "incurable diseases" on the blackboard, Liu Qing grabbed the back of his head and asked.

Li Fanyu rubbed his chin with his fingers and tried to say what he thought.

"If so...... Wouldn't it be better if we directly replaced these submarines with a more direct power scheme?"

"Brother Fan. ...... you mean?" Liu Qing was stunned for a moment, a little incomprehensible.

Li Fanyu got up, dragged a large whiteboard with his hand, picked up a whiteboard marker, and drew a general structure diagram of a Kilo-class submarine on the seat.

Then he wiped out the large diesel engines, circulation pumps, transmission gearboxes on Kilo-class submarines. In the power compartment of the submarine, where the "belly" has been hollowed out, an icon representing the battery is drawn, and after that, two solid lines representing cables are drawn directly to the motor.

But when it came to the propeller, he frowned again.

After thinking for a while, his eyes lit up, as if he had figured out the overall situation, and simply wiped the propeller and changed it to another pump body marker.

"The main sources of noise in submarines are the airborne noise generated by the mechanical operation of the cabin, the structure-borne noise generated by the propeller propagation caused by the vibration of the mechanical structural parts, the rotational noise of the propellers, and the hydrodynamic noise caused by the flow of water passing through the hull. But after so many days of investigation, I think the first three are the most important. So, let's start here!"

He threw the whiteboard marker on the ground and said categorically.