Chapter 490： sound-absorbing tile

In the battle between submarines and surface ships, submarines are always at a disadvantage. For submarines, continuously improving their mute performance is the basis for their continued existence. When the underwater sound noise can be compared with the ocean background noise When it is comparable, it will be extremely difficult for surface warships to detect underwater submarines.

It is from this perspective that in later generations, active sonar will gradually develop, and even active towed body sonar will appear, all to fight against new-style submarines.

The use of active sonar, is to pay a certain price. The war is fair, how much you pay for how much benefit you get. Turning on the active sonar itself is a dangerous move to kill yourself. After all, the submarine is hiding in the dark. When the active sonar is turned on, it is easy to be discovered by the submarine. On the battlefield , whoever turns on the active sonar will be attacked first!

Therefore, if it is really a battle, the ships with active sonar are relatively low-value frigates. The active sonar is actually intended to be desperate. The 10,000-ton warships, or even the tens of thousands of aircraft carriers, will not come. take the risk. This is a life-and-death fight.

But now, it doesn't matter. Until now, the United States and the Soviet Union have not really torn their faces and staged a third world war. In this case, the two sides are still confronting in the style of the Cold War. The rules, for example, for submarines that come within the confines of their fleet, are definitely a slap in the face of the underdogs. And as long as the opponent surfaced, the confrontation was over.

Turning on the active sonar is like playing countless flashlights, illuminating the underwater, I can't believe that you can't find you!

Americans are crazy! Just when the sonar crew discovered that the active sonar was turned on by the American naval formation, Neil Geyev also began to respond and dive!

Dive? Is it the way to deal with active sonar? of course not! The detection distance of active sonar can even exceed 20 kilometers, and the depth of diving is limited to a few hundred meters.

But now, diving can be used to deal with American detection!

Dive urgently! Following the order of Neil Geyev, the rudder surface of the submarine's horizontal rudder began to turn sharply. At the same time, all the submariners who were not on post were quickly running from their positions to the front. The torpedo cabin!

The bow of the boat began to go down quickly, the huge submarine, the hull tilted, and continued to dive!

The hull churned up the water, and there might have been extra noise, but for now, not so much!

At this moment, several sonar waves hit the body of the huge 949-class submarine.

If it is an ordinary submarine, when it is hit by active sonar waves, the hull will vibrate, and the cavity effect will amplify the sound. The submarine soldiers inside can clearly hear this terrible sound. For them, The detection of active sonar means the arrival of the torpedo at the next moment.

But now, when the active sonar wave hits the boat, it first comes into contact with the outer shell of the submarine, but before it touches it, it encounters something soft.

Muffler tile!

The 150mm-thick sound-absorbing tiles made of styrene-butadiene rubber are laid on the outer shell of the submarine and have a complex acoustic structure inside. When the active sonar waves come over, the sound-absorbing tiles absorb most of the sonar waves!

The Soviet Union has always used double-hulled submarines. The inner and outer shells of this submarine are covered with sound-absorbing tiles. The outer sound-absorbing tiles are mainly used to deal with active sonar, and the inner sound-absorbing tiles are mainly used for themselves. Noise reduction!

Moreover, the sonar wave that came this time was not the sonar wave from that perverted aircraft carrier, but the sonar wave of an ordinary destroyer. After absorption, the reflected back was quite small!

The personnel inside the submarine could hardly hear the outer sonar waves. Only the sonar operator quickly took off his earphones, covered his ears, and cursed in a low voice, "Damn Americans!"

The principle of sonar is to amplify the sound signal. At this time, the amplified active sonar signal makes the ears of the sonar operator extremely painful.

Dive, keep diving! Just like having a golden bell hood and an iron cloth shirt, the 949-class submarine endured a few sonar waves and finally dived into the water at a depth of 150 meters.

"Balance the hull, calibrate the course, and move on," Nilgayev said.

The sonar operator put on his earphones again, and the noisy active sonar sounds have all disappeared, except for the gurgle of the unique ocean background noise!

"We have successfully entered the pycnocline," the sonar operator reported.

Densitoclines!

There is salt in seawater. With the difference in salt content, the density of seawater is also different. Generally speaking, this density increases suddenly with the increase of depth, and the water layer where the density of seawater suddenly increases in the vertical direction is called Densitocline.

This is the dividing line where the density of seawater varies greatly between surface and deep layers. The low-density seawater will gather on the high-density seawater, and the upper part will be lighter and the lower part will be heavier, so that the seawater will be distributed in layers. Between the upper and lower layers, a barrier is naturally formed, called the densitocline. This depth is different. In the ocean, it may be more than 1,000 meters, while in the offshore sea, it may be more than 100 meters deep.

These hydrological conditions need to be surveyed in advance to know. Submarine countries all have marine research ships By the argument of investigation, it is actually preparing for the action of submarines.

The pycnocline is of great significance to the navigation of submarines. Because this clamshell will refract sound wave propagation! That is to say, the sound waves of the active sonar launched by the US warships on the water at this time were all blocked by the jump! Submarines can avoid detection by hiding under the jump!

Moreover, the clamshell is relatively stable, and the submarine knows that it can sit on it and flow with the sea water, saving fuel. Therefore, the densitocline can be said to be the "liquid seafloor".

In addition to the pycnocline, various complex hydrological environments such as the thermocline, the halocline, and the sonocline can also be used underwater, and here, the densocline is the most suitable.

Safe and steady, under this water, there is nothing to be afraid of!

"Full speed ahead," Nilgayev ordered. Now that it has entered the densitocline, the active sonar waves detected above cannot come down, and the noise from its own submarine cannot be transmitted, so it is the most important to take advantage of this opportunity to get out of here quickly. Just a voyage , It has been proved that the US aircraft carrier formation cannot effectively detect its own nuclear submarines. If a war really starts, the 949 class will become a stealth killer! (To be continued.) To find this site, please search for "" or enter the URL: