Iron Sonata of World War II

"Uncle Paul, you know that if you ignite a cotton ball soaked in kerosene in the air and throw it into a beaker filled with oxygen, the kerosene cotton ball will only burn violently and not explode, right?" Helena said, "Then why don't we Let the torpedo combustion chamber ignite in the air first, and then slowly introduce oxygen? We can use a small compressed air tank to be responsible for the ignition in addition to the main air tank containing compressed oxygen."

After hearing this, Bainke's eyes suddenly lit up. Although he didn't know whether the plan would be feasible in the end, it sounded very reasonable.Anyway, it has already failed so many times on oxygen torpedoes. Even if it is not feasible in the end, it is just one more failure. If it is feasible, then Germany can directly lead the world in torpedo technology by one position.

Bainke is a man of action, and he is impatiently preparing to put it into practice. After repeatedly reminding Helena not to tell the fourth person about the idea, Bainke bid farewell to Sektor and his daughter.

Helena showed a satisfied smile on her face as she watched Bainke walk away with a hasty pace. She knew that she had achieved her goal today.

Chapter 6 The Volunteer Takes the Bait

In the first half of 1921, for the German Navy, two major events occurred. The first one was that the ACC (Allied Powers Supervision Committee) finally approved the construction of a cruiser equipped with three twin 155mm naval guns and a displacement of 6000 tons.Another thing is the success of the preliminary tests of the oxygen torpedo.

Because of these two incidents, Helena suddenly became a popular person in front of Lieutenant General Bainke. Lieutenant General Bainke is actually 52 years old, but the so-called happy event is full of energy, and he is always called "little Helena" Uncle Paul, Uncle Paul," Bainke felt that he was still young and could fight for the Navy for another 20 years.

"Thank you Uncle Paul for the model airplane! I really like it!" Helena gave Behnke a big hug. "What's up with the little angel today?" Bainke said, stroking little Helena's head.Yesterday he just sent someone to give Helena a very exquisite 1:200 model of the wooden battlecruiser Derfflinger.

"Uncle Paul, is it possible for Germany to participate in the Washington Naval Conference? It is also fine as an observer country." Helena asked.

"The navy hopes to participate, but there is no chance." Bainke couldn't help but sighed.

He also hopes that Germany can participate in the International Naval Conference.There are two reasons. On the one hand, there are huge differences between Britain, the United States, Japan, France and Italy on the naval arms control treaty. This difference is conducive to Germany looking for opportunities to relax the shackles of the Treaty of Versailles. On the other hand, even if the restrictions on the German navy cannot be relaxed , it would be nice to show your face at international conferences, now not only the German navy, but the whole of Germany is about to become an international outcast (in the last plane, the Soviet Union and Germany signed the "Rapallo Treaty" in 1922, and Germany in 1925 Signed the "Locarno Convention" with Britain, France and other countries, after which the relationship between Germany and the major powers in the world began to return to normal), even if it is just showing up in important international conferences, it will undoubtedly be a great benefit for accelerating Germany's return to a normal country!

"Uncle, I think we have a chance!" said Helena. "Remember the oxygen torpedo we just successfully tested? I think that could be our ticket."

"You mean to use oxygen torpedo technology in exchange for support from other major powers? This is our top-secret military technology!" Behnke was a little surprised.

"It is precisely because it is a top-secret military technology that it can be used as a bargaining chip! Besides, the principle of the oxygen torpedo is actually very simple. We just thought of it before other countries. It's worthless, so we can take this opportunity to sell the oxygen torpedo technology at a good price." Helena said nonchalantly.

"Actually, you want to transfer the technology to Japan in exchange for Japan's support, so as to open the gap?" Bainke immediately understood Helena's plan.

"Yes, on the one hand, there is neither actual conflict nor potential conflict between the Japanese navy and the German navy. Handing over technology to Japan will not threaten Germany at all, but will threaten Germany's potential opponents; Torpedo technology is the most eager. After successive victories over the Chinese and Russian navies, it is inevitable for the U.S. Navy to become a potential opponent of Japan. Since the strength of the United States is far above Japan, the only thing Japan can hope for is a The surprise victory in the Russo-Japanese War played a huge role in the Sino-Japanese War and the Russo-Japanese War, which made Japan pay more attention to torpedo tactics than other countries, and perhaps only the Italians can match it.” Helena After finishing speaking in one breath, he quietly looked at Lieutenant General Bainke, waiting for his answer.

"What you said makes a lot of sense." Bainke thought for a long time, and he was obviously moved by this matter. "But this matter cannot be decided by me alone. It needs to be discussed within the Navy. How to maximize the benefits that can be exchanged also needs to be carefully planned."

"That's right, let's make the bait more fragrant, and I believe the Japanese fish will bite." Helena showed a smile on her face that the plot was about to succeed. "Waiting for your good news, Uncle Paul."

Chapter 7 Hydrogen Peroxide

Yusaburo Kato, the Minister of the Sea of ​​the Japanese Temple Cabinet, who took office in 1916. This famous naval veteran who served as the deputy of Heihachiro Togo in the Russo-Japanese War was in very bad physical condition at this time, with a pale face and high cheekbones. , The whole person exuded a strong breath of death, as if a zombie crawling out of an ancient tomb would turn into a pile of bones if hit with a stick.

In the last plane, Yusaburo Kato will attend the Washington Conference as a plenipotentiary representative of Japan in a few months.Afterwards, he will serve as the Prime Minister of Japan because of his outstanding performance at the Washington Conference, but only in the second year of his tenure as Prime Minister, that is, 1923, the old man nicknamed the "Candle Prime Minister" will die of illness in office.

Now, Yusaburo Kato is sitting in the back of his office, a sickly look on his face, evidently the weariness of the months-long preparations for the Washington meeting is taking its toll on the aging man.

"Master Marine, urgent call from Kiel!"

"Kiel? German Kiel?" Tomosaburo Kato was a little surprised. Since the end of World War I, the German navy, which was once the second largest in the world, seemed to have suddenly become invisible. No wonder Tomosaburo Kato was surprised.

"Read it!" Kato raised his hand to signal.

As the content of the telegram was read out, Yusaburo Kato stood up with his chair supported, and his lifeless face seemed to suddenly come alive, with expressions of surprise, excitement, and entanglement alternately appearing on his face.

"Call the relevant personnel immediately, there is an emergency meeting." Kato finally said.

It turned out that a few days ago, Germany suddenly invited the military attache of the Japanese Navy in Germany and demonstrated a new type of torpedo with a range at least three times that of the current product in the North Sea. The military attache in Germany immediately realized that Germany had mastered the technology of oxygen-powered torpedoes The key to technology.After watching the torpedo demonstration, the military attache stationed in Germany was scratching his head. As soon as he disembarked in Kiel, he sent a telegram to Japan overnight without even having time to return to Berlin.

……

A few hours later, a group of senior Japanese navy generals gathered in the conference room, and the attendant read out the telegram just taken under Kato's gesture. The conference room was silent at first, and then it became noisy like boiling water.

In the end, Kato raised his hand several times, and the venue gradually became quiet.

"Everyone knows that the national power of the Imperial Kingdom is far weaker than that of the United States (the United States is called the United States in Japan). You all hope that the Washington Arms Control Conference will allow our army to obtain [-]% of the share of the United States, otherwise there will be no chance of winning naval battles in the future." Kato Said slowly.

All the admirals present nodded their heads.

Kato Yusaburo paused for a while, and then said, "However, the arms control meeting is also a meeting of national power. Do you think that this meeting will give us a few percent of the US Navy?"

Seeing that everyone was silent, Kato sighed and said, "As the plenipotentiary representative of our party participating in the arms control meeting, I privately think that getting [-]% of the share of the Mi Army is already the limit, and more shares cannot be achieved by manpower. Just after Kato finished speaking, the venue immediately became noisy again. Obviously, the [-]% share is already lower than the bottom line that Japan thinks it can fight.

After everyone was quiet, Kato went on to say: "Even if there is no treaty restriction, do you think our finances can support the current shipbuilding speed for a few more years? I am afraid that the Mi Army will not need to do anything. The finances will first put our fleet It was sunk. Germany has hinted us this time that if Japan is not interested in oxygen torpedoes, they will find the next buyer, most likely the United States. Although the United States may not necessarily support them to participate in the Washington Conference, but in terms of paying for technology But never stingy."

As soon as this remark came out, the venue immediately exploded.You must know that the United States is now constantly urging Japan to dissolve its alliance with the United Kingdom, and the United Kingdom seems to have no interest in renewing the alliance. Once the Anglo-Japanese alliance collapses, Japan's good days of pretending to be powerful will be gone forever. If there is a conflict with the United States in the world, Japan will not be able to get the support of Britain like it did during the Russo-Japanese War.

All the admirals dare not imagine how Japan will deal with the giant on the other side of the ocean alone if the lightning strike war that Japan is proud of is overtaken by the US military.

"At present, we have no choice but to support Germany's participation in the Washington Conference. It is imperative to exchange for Germany's torpedo technology, but we must make Germany promise not to transfer the technology to a third country! Now we are still allies with the United Kingdom, and we are still allies with the United Kingdom. Let’s communicate, it’s not difficult for Germany to participate in the meeting as an observer country, at worst, the meeting will end with the countries signing a supplementary agreement with Germany, but the transfer fee can’t be left to the Germans, 360 million pounds, can they say it?” Yusaburo Kato finally set the tone for the meeting.

If 360 million pounds were placed before World War I, you could buy a Queen Elizabeth-class super dreadnought with a unit price of 240 million pounds. The British pound is still a huge sum of money. You must know that the battlecruiser Hood with a standard displacement of 360 tons is only more than 4 million pounds!

But the so-called skyrocketing price, sit back and pay back the money.After a lot of verbal bargaining, Germany and Japan finally reached a secret agreement: Germany transfers all the technology of the oxygen torpedo to Japan, and promises not to disclose this technology to third countries, and Japan needs to pay Germany a technology transfer fee of 220 million pounds , and pledged to fight for Germany's participation as an observer state at the Washington Conference.

……

"Uncle Paul, forget about the scum of oxygen torpedoes, hydrogen peroxide torpedoes are the way to go in the future!" Seeing Bainke's somewhat regretful expression, Helena comforted her and reached out to try to pat him. Bainke's shoulders, but for the seven-year-old Helena, Bainke's shoulders were obviously too high, so Helena had to pat Bainke's back instead.

Helena dared to take out the oxygen torpedo to exchange benefits with Japan, so of course she had a hole card.

Compared with compressed pure oxygen, high-concentration hydrogen peroxide is undoubtedly a more suitable oxidant.

First, hydrogen peroxide can be stored under normal pressure and does not need to be pressurized like pure oxygen, which greatly improves safety;

Second, high-concentration hydrogen peroxide itself will release a lot of heat when it is decomposed into water and oxygen. The decomposition of 1 kg of 90% high-concentration hydrogen peroxide can produce 1700 liters of water vapor with a temperature of up to 740 degrees and 432 grams of oxygen. High temperature Steam and gas can work together to drive a turbine;

Third, if hydrogen peroxide is in contact with kerosene mixed with a manganese-based catalyst, it can be ignited directly by itself, which can save the ignition device;

Fourth, if seawater is added as a coolant in addition to high-concentration hydrogen peroxide and kerosene, a three-component torpedo can be made. (If you have never heard of what a hydrogen peroxide tri-component torpedo is, please Baidu the 65 series "Fat Girl" torpedo on the "Kursk" nuclear submarine. It is her, it is her, it is her).

Well, although the reputation of hydrogen peroxide torpedoes is not good in terms of safety, such as sinking the conventional submarine "Sitton" in the UK, and the nuclear submarine "Kursk" in Russia, but Hydrogen peroxide is safer than compressed pure oxygen.

You should know that several accidents of hydrogen peroxide torpedoes were on submarines. Once high-concentration hydrogen peroxide accidentally comes into contact with metal oxides, it will immediately decompose and generate a lot of oxygen.In a closed space like a submarine, the high-concentration oxygen cannot be diffused, and the heat released is also not released. Once the local high temperature and high-concentration pure oxygen encounter combustibles, it is no wonder that nothing happens.

However, surface ships all use open launch tubes. High-concentration hydrogen peroxide can also be kept away from torpedoes at ordinary times. It can be placed on the ship away from combustibles, and it can be refilled when combat is required, which is much safer than pure oxygen.In Helena's memory, the safety record of the hydrogen peroxide ethanol torpedoes that the United States served in 1944 is still good.

With this analysis, Helena is still ready to activate the hydrogen peroxide torpedo technology tree.

The development project of the hydrogen peroxide torpedo was handed over to Dr. Helmut Walter by the Navy. As soon as Helena saw the name, Helena knew that she had chosen the right person. This buddy is also a fierce man in history. Walter is the most worthy of boasting The achievement is to design the famous "Walter Turbine"!

With the Walter turbine, Dr. Walter created the world's first AIP (air independent) submarine in 1940 - the V80!But this is not the most violent, the most violent is that Walter's submarine uses hydrogen peroxide as a combustion aid!During a sea trial in 1940, the V80 broke the world record with an amazing underwater speed of 28 knots.

However, Walter's AIP system has a short trouble-free life and poor safety. Therefore, only 10 German AIP submarines were built for testing during World War II, and none of them were put into actual combat.

Thinking of this, Helena couldn't help complaining that Dr. Walter's brain can't turn, and holding such a magical weapon, what kind of AIP submarine is it used for? You have to worry about being blown to death by yourself when you sleep.Wouldn't your Walter turbine be nice to power your torpedoes?In torpedoes, the short trouble-free life is not a problem at all. After all, the working time of the torpedo engine is only a few ten minutes at the top.

Fortunately, under the influence of Helena's butterfly effect, our Dr. Helmut Walter in this plane finally walked on the sunny avenue, and Helena couldn't help but show a gratified expression.

With the "Treaty of Versailles" under pressure, the current German army has too little room for maneuver, and there are too few things to say. Our Helena can only go to the naval technology tree.

Although the protagonist of this book has a system, the existence of the system will not be too high. The main purpose is to provide a reasonable source for the protagonist's information and design. In addition, it is unlikely that there will be too advanced technology in this book, at least not by a large margin. At that time, the manufacturing capacity of the basic industry, although this may weaken a lot of cool points, but designing a weapon itself is dancing with shackles. Helena has really tried her best, and I hope everyone understands.

Chapter 8 The Washington Society

In order to squeeze into the Washington meeting, Germany certainly would not put all its eggs in the same basket as Japan, so the German ambassador to the United States begged to meet US President Warren Gamelier Harding at the White House.

"Dear Mr. President, I am glad to hear that you hope to turn the upcoming international conference in Washington into a broadly representative peace conference. Germany deeply reflects on its previous war behavior and hopes to become a peace-loving country again by participating in this conference. A member of the country" the German ambassador kept his profile low.

"In the last war, Britain and France were the main victims of the war. Germany should seek understanding from Britain and France, not the United States." President Harding obviously lacked interest in bringing Germany into the Washington Conference.

"If the United States can help Germany to participate in the meeting, the United States will gain the friendship of Germany." The German ambassador said.

"What can Germany's friendship bring to the United States? We are not interested in the balancing act you played in Europe. Besides, Germany can't even pay the reparations to Britain and France. What's the point of attending the meeting?" President Harding Apparently a little impatient, he picked up the hot coffee in his hand and blew leisurely, saying: "Ambassador, please go back. France will not agree to Germany's participation in the meeting. There is no need for the United States to help Germany on this issue."

"Thank you for the president's meeting. I believe that the politicians of the Democratic Party will be interested in the matter of Cary Fulton Phillips. Let me leave." The German ambassador slowly spread his cards and made a gesture to leave.

However, as soon as these words came out, President Harding immediately jumped up like a cat whose tail was stepped on, and the coffee cup in his hand fell to the ground and shattered, and the hot coffee splashed on President Harding's hands and body. But he didn't realize it.

Faced with President Harding’s expression as if he wanted to eat people, the German ambassador said calmly: “Germany and the United States are friendly countries. Germany does not want to see the president of a friendly country get involved in scandals. Mr. President, don’t let Germany down. friendship."

"The United States will do everything possible to allow Germany to participate as an observer. Mr. Ambassador, please go back." President Harding sat back in his chair as if he had collapsed.

It turns out that after Harding married Florence, the daughter of a wealthy businessman, he did not restrain his romantic personality, secretly kept mistresses outsourced, and had an illegitimate daughter.If this is the case, although it is not an honorable thing, it is not enough to shake Harding's position as president. The bigger problem is that Harding seems to have a special interest in married women. In 1905, Harding hooked up with Married to Cary Fulton Phillips, the relationship lasted until the 1919 presidential campaign.After Harding became the Republican candidate, the Republican National Committee was afraid that the scandal would be exposed, so it paid a large amount of hush money to let the Carys go to Japan for a "long-term tour".

Harding thought hard and couldn't figure out how the scandal was known to the Germans. After all, things like time travelers were beyond his cognition.Although I don't know how the Germans knew about their scandal, Harding understands one thing, that is, the Democrats must not let this matter know, otherwise his dream of being re-elected as president will be shattered in advance.

If Helena knew Harding's mental activities at this time, Helena would definitely roll her eyes at Harding, because in 1923, President Harding would die of a stroke while in office, so Harding's re-election dream is destined to be It can't be realized.It is said that after Harding's death, due to the categorical refusal of the president's wife, Florence, the autopsy was ignored. Until the 21st century, some people suspected that the president's wife hated Harding's affair and poisoned her husband to death.

Regardless of whether President Harding is gnashing his teeth with hatred behind his back, with the support of the United States and Japan, the matter of Germany's participation in the Washington Conference has basically been settled.When the news came back to Berlin, the German political circles were jubilant, because this was the first time since 1918 that Germany had re-attended an important international conference, which was undoubtedly a good start for breaking Germany's diplomatic isolation.

……

Looking at Americans' evaluations of previous presidents, Harding is notorious. In the polls of "the worst president in American history", Harding ranked among the best every time, and won the crown three times.This is not only because of Harding's endless lace news and moral taint, but also because of Harding's negligence during his tenure. During Harding's tenure, it was common for him to drink whiskey and play cards with his colleagues at work.However, Harding still has one commendable achievement, that is, he proposed the initiative and organized the Washington Conference.

On November 1921, 11, at the initiative of US President Warren Gamelier Harding, the Washington Conference was held in Washington, the capital of the United States. The United States attended the meeting, and Germany participated as an observer.Under the flashing lights of countless reporters, representatives from various countries entered the venue one by one. The venue was decorated with flowers and palm leaves symbolizing peace. order and restore peace to the world..."

Harding's speech ability is good, and he is very involved in speaking, but the interest of the representatives of various countries is obviously not in listening to Harding's speech.In fact, although the meeting agenda was complex, there were actually only two core topics. One was the re-division of the Far East by the great powers, and the other was the readjustment of the powers' maritime military strength.Now the representatives of various countries are gearing up, hoping that their countries can gain something from the meeting.

Chapter 9 Drainage tricks

At the Washington meeting on this side, the verbal war between representatives of various countries is in full swing.

At the same time, Germany on the other side of the Atlantic is not idle. Now various naval designers are working on the detailed design of the 6000-ton new cruiser that has just been approved by the ACC. Previously, several designers submitted to the Navy under the influence of Helena. His plan is actually just a design draft, and if he wants to turn the design draft into a design drawing that can be delivered to the shipyard for construction, it is not something that a few designers can do in a few weeks.In the middle, a lot of scientific experiments, program demonstration and design refinement work are needed.

Knowing that the devil lies in the details, Helena will naturally not let go of the opportunity to further optimize the design. With Behnke's green light, Helena has become a frequent visitor in the design office. At first, most designers didn't care. They believed that General Bainke allowed Helena to visit only to satisfy "the curiosity of a friend's daughter."But soon they were conquered by the "gifted girl" Helena's "unconstrained ideas", especially after these ideas were proved feasible by calculations and experiments.

Regarding this point, Helena actually blushes a little bit. After all, Helena in her previous life was just an ordinary technician in a small factory. In terms of professionalism, she was more than a block behind these professional ship designers who have seen big winds and waves. .Helena's so-called "genius idea with a flash of inspiration" is often the experience of countless designers in later generations after hard work.In fact, looking at the history of technological development, most of the so-called "light flashes" by designers will be thrown into the garbage dump after being slapped in the face by experiments, and only a few of them are proven to be effective and feasible.

Closer to home, in order to further enhance the combat effectiveness of the new light cruiser, the designers and Helena really spent a lot of effort.The main measures are summarized as follows:

The first one is to play tricks on the displacement.

Don't laugh, everyone, this simple and rude method is the most effective way to improve the performance of a single ship under the restrictions of the treaty.And the specific method of playing tricks is divided into two types: over the standard and over the standard.

The so-called exceeding the standard is actually playing a rogue.In other words, I blatantly exceeded the standard, you come to arrest me, anyway, you can't find evidence.It should be known that before the advent of 15D laser scanning technology, the traditional geometric measurement method was used to measure the displacement of ships. However, for a 155D hull with complex curved surfaces, it is really not easy to measure it more accurately.Historically, Japan has described the top class with 11000 8500mm main guns and a displacement of 5 tons as an "155-ton light cruiser". There is no actual handle. After the treaty expired, Japan carried out a large-scale modification of the top class, replacing five triple-mounted 5mm guns with five 203mm guns, and turned it into a heavy cruiser with a displacement of more than 12000 tons!Other countries have more or less exceeded the standard of displacement, but not as much as Japan.

The so-called hidden excess is to take advantage of the loopholes in the definition of standard displacement.According to the definition of "standard displacement", the standard displacement includes the hull, machinery, armaments, full personnel and corresponding ammunition, supplies and fresh water, excluding fuel oil, lubricating oil, and spare boiler water.It seems that the definition is very strict, but it does not mean that there are no loopholes to exploit.For example, some secondary equipment and auxiliary weapons are not fully installed during service, but there is room for improvement and installation positions.Anyway, after serving, you can use the method of moving mice to buy slowly. Add an anti-aircraft gun today, add a few pieces of equipment tomorrow, and expand the lightning protection compartment the day after tomorrow.

In Helena's memory, the Navy of the Weimar Republic in the last plane also played this set of over-standard games. For example, the Königsberg-class light cruisers and the Deutschland-class armored ships all exceeded the standard by more than 10%. When building Emden, the Germans were still too naive and did not understand the complexity of the world. They were too honest (only 6000 tons were used for a displacement of 5600 tons).

Therefore, in this plane, Germany did not dare to fight openly like Japan, but with the instigation of Helena and the secret support of the navy, the new cruiser still surpassed the standard in the previous plane ahead of schedule.In order to save displacement, the installation of torpedoes and medium-caliber secondary guns will be suspended when the new ship is in service, but even so, it is estimated that the standard displacement will still reach 6800 tons when it is completed, which is basically the same as that of Königsberg in the Weimar Republic in the previous plane. Class light cruisers have about the same displacement.Based on the experience of the previous plane, Helena believes that this level of displacement will not cause the Allied Powers to turn the tables.

Because the ACC (Allied Supervision Committee) is more vigilant about the move to increase the firepower of the new German ship (in the last plane, Germany once proposed an eight-gun plan with four dual-mounted turrets, but it failed in the ACC. In this plane, the ACC The four-seat twin-mounted plan was also rejected, and only the three-seat double-mounted six-gun plan was released).So next, Helena and the designer can only devote all their energy to further strengthening the speed and protection of the new ship.

Chapter 10 Drag Reduction Ace

There are two ways to increase the speed of a ship, one is to increase the power output, and the other is to optimize the drag reduction line.

The path of increasing the power output is naturally the easiest way. The so-called miracles with great force, as long as the power is sufficient, you can fly to the sky by moving bricks. However, when actually designing a ship, increasing the power output is not an easy way to go.Because the relationship between power and speed is not proportional, but proportional to the cube of the speed, that is to say, if you want to increase the speed to twice the original speed, the power needs to be increased to eight times the original!If the high speed is obtained entirely by increasing the power output, it will inevitably lead to a rapid expansion of the volume and weight of the power system!

In the case that the structural weight of the ship and the weight of the weapon cannot be greatly reduced, more weight is allocated to the power system, which means that less weight can be allocated to the protection.Moreover, a larger power system means a larger and longer power cabin. It must be known that in the core area of ​​​​the ship that needs armor protection, the largest volume is not the ammunition depot, but the power cabin.Now, here comes the problem, you use less protective weight to protect a larger core module, and the reduction in protective strength is an inevitable result.For example, the Agano-class light cruiser of the old Japanese Navy in the last plane is also a 6-ton light cruiser with six 6000-inch main guns. In order to achieve high speed, 10 horsepower was stuffed into the small hull. Level of power, although it ran a high speed of 105500 knots with 35.82 horsepower in the test voyage, but the price is that its vertical main armor belt is only 60mm, and the horizontal armor is only 20mm. This protection is enough to deal with the firepower of destroyers. The gunfire starting at an inch is basically the same as streaking.

Helena wants the new cruiser to have a high speed, but also does not want to protect herself from streaking. Optimizing the drag reduction line has become the only choice.This is forcing me to do my best, Helena thought.So the three aces were played by Helena one by one.

Helena's first ace was called the SV bulbous bow.We often see warships in documentaries riding the wind and waves on the sea. At this time, the bow of the ship will hit a huge splash, which looks majestic visually, but this beautiful splash is not a good thing for the battleship. According to the law of energy conservation, the ship The energy of the waves caused by sailing will not be generated out of thin air, but can only come from the propulsion power of the ship, that is to say, part of the propulsion power of the ship is uselessly consumed in the process of exciting waves. This resistance Known as wave-making resistance.In order to deal with this kind of wave-making resistance, people came up with the method of installing a protruding bulbous nose below the waterline of the bow. This bulbous nose will also stir up water waves, but the wonderful thing is that the trough of the water wave raised by the bulbous nose is just right. It is the crest of the water wave raised by the bow of the original ship, and the two phases cancel each other out, so the wave at the bow becomes relatively flat, and the wave-making resistance is greatly reduced.A well-designed bulbous bow also rectifies the bow water flow and improves the effect of the bilge vortex, which further reduces resistance.

The bulbous bow shape that appeared earlier was the drop-shaped bulbous bow, which had been used on large warships during World War I (such as the Delaware-class battleship of the US Empire), and the bulbous bow was more widely used on ships in World War II , but what Helena offered is a more advanced SV bulbous bow, its bow column is S-shaped, and the lower part of the bulbous bow is V-shaped. It was only invented. The biggest advantage of the SV bulbous bow is that it has a very wide range of adaptability. It can reduce wave resistance at high speed and reduce bilge vortex at low speed. It is less affected by wind and waves than the drop-shaped bulbous nose. Warships need to fight in the rough North Sea and the often frozen Baltic Sea, and the SV bulbous bow is undoubtedly a very suitable choice!

Helena's second trump card is called the Fillet Stern.

When it comes to the shape of the stern, it can be roughly divided into three types, oval stern, cruiser stern, and square stern.

The elliptical stern is famous for the elliptical shape of the aft deck, and the end is exposed to the water surface. It is mainly used in early ships, because of the disadvantages of poor drag reduction, low utilization of stern space, and lack of protection for propellers and rudders. Except for some barges which are already relatively rare.

As the name suggests, the cruiser stern is a stern shape that was first applied on warships, and was later widely used in civilian ships (however, many civilian ships that use cruiser sterns cut off a section of the tail tip to reduce weight and improve space utilization).The characteristic of the cruiser stern is that most of the stern is immersed in the water, and the waterline surface of the stern is relatively sharp and thin. Compared with the elliptical stern, this kind of stern prolongs the length of the waterline, reduces the cruising resistance, and also allows the propeller and stern rudder to gain Better protection is one of the stern shapes of large warships in the two world wars.

However, despite the various advantages of the cruiser stern, Helena still prefers the most widely used square stern on a battleship of the cruiser class.The characteristics of the square stern The transverse section of the stern is close to a square, while the slope of the longitudinal section is gentle. This is a stern shape suitable for high-speed sailing. The main principle is that when the water flows through the stern at high speed, it will not gather immediately, but It will continue to flow backward for a certain distance, which is equivalent to adding an invisible long tail to the ship, forming a virtual streamlined shape, which is equivalent to increasing the aspect ratio without increasing frictional resistance.Of course, the square stern also has disadvantages. Its fuel economy at low speed cruising is slightly worse than that of the cruiser stern.However, this is not without a solution. Let the transition between the stern and the bottom of the ship and the side be smooth, so as to alleviate the adverse effect of the lower economy of the stern when cruising at low speed, and also reduce the stress concentration caused by the knuckles.In the previous plane, the rounded stern was very common on Soviet destroyers and cruisers during the Cold War (such as the well-known modern class).Of course, due to the higher and higher requirements of warships for stealth, most of the tails of destroyers and frigates built by various countries in the new century have become sharp-edged shapes, but the rounded sterns still continue to exist tenaciously (such as the newly commissioned Shandong aircraft carrier).

Helena's third trump card is the tail wedge/board combination.

The tail wedge/plate is a drag-reducing appendage installed at the stern of the ship, which is a combination of the tail wedge and the stern corrugation plate.

Among them, the tail wedge is a wedge-shaped block installed on the stern of the ship. The thickness of the mid-longitudinal section is the largest, and the thickness gradually decreases toward the bilge on both sides, and finally merges smoothly with the bilge.The tail wedge was first applied to the German Type 34 destroyer in the last plane, and achieved a good drag reduction effect. .The stern corrugation board is a more popular drag reduction method after the war. A short board extending backward is installed near the stern board near the bottom plate of the hull, generally at a certain depression angle.

The role of the tail wedge and the stern pressure wave plate is generally to rectify the tail water flow, increase the tail pressure, and extend the extension of the high-speed water flow behind the stern to increase the "imaginary length" of the hull and reduce the adverse effects of the chicken tail flow.Combining the tail wedge and the tail pressure wave plate becomes a "tail wedge/plate combination". The "tail wedge/plate combination" combines the advantages of the two, which can not only reduce the bending moment on the tail pressure wave The resistance effect is better than simply installing a tail wedge or a tail pressure wave plate.

The three trump cards are used together. Through the design consultation function in the system, Helena believes that the drag reduction effect of the new cruiser at high speed will exceed 30%. That is to say, at high speed, the new cruiser only needs less than 70% of the original power output. The same speed can be obtained, which greatly saves the weight of the power system and shortens the length of the core cabin.With this level of guarantee, Helena expresses her confidence to achieve the same high speed of 35-36 knots as Agano on the premise of ensuring sufficient protection strength of the core cabin!

However, the "rounded square stern" and "tail wedge/plate combination" are drag reduction measures optimized for high-speed navigation, and the resistance at low speeds is a little larger than that of cruiser sterns, but relying on the rectification and bilge vortex reduction of the SV bulbous bow As a result, the cruising resistance of the new cruisers is still slightly lower than that of similar ships of this era.