Daming 1805

When Zhu Jingyuan woke up in the morning, sisters Xiaona, one on each side, leaned on her body and slept soundly.

Usually they should have gotten up at this time, but now they still haven't woken up, probably because they were really tired last night.

The daily military training of the Ming royal family can be suspended for one day during marriage and concubinage.

Even maidservants who are formally lucky are counted, because in theory, having children is much more important than military training.

Zhu Jingyuan looked at the two girls beside him, hesitated for a while, and finally did not wake them up.

He closed his eyes and hugged the two of them, and went to sleep again.

It wasn't until after nine o'clock in the morning that the three of them got up from the bed and went to the restaurant for dinner together.

Both sisters An Xiaona were slightly injured, and their walking postures were a bit unnatural.

However, this unnatural posture, in the eyes of the other maidservants, reflected the word - envy.

After Zhu Jingyuan had breakfast, he took Sister An Xiaona to meet the Supreme Emperor:

"Grandpa, my grandson took in two concubines yesterday, and I'm going to confer them as talented men of the Great Food King. Today I bring the two of them here to pay you a formal greeting."

An Xiaona was more lively when she was with Zhu Jingyuan, but she was very disciplined when she was in front of other people.

Now let's salute Zhu Zhongliang honestly and respectfully.

Zhu Zhongliang took a look at Sister An Xiaona for a while, then waved his hand very casually and said:
"Understood, you two go and rest first, Jingyuan stay and talk with me."

The sisters An Xiaona immediately saluted again, and then walked out of the room with small steps.

Zhu Jingyuan watched the two of them leave, and sat directly opposite Zhu Zhongliang.

Then I heard Zhu Zhongliang seem to be quite unhappy saying:
"Shouldn't your boy accept two more prince concubines now?"

The prince's concubine's room, by default, is the kind that finds a Daming person, and the child born can succeed to the throne.

In the eyes of traditional natives like Zhu Zhongliang, not to mention orchids like Sister An Xiaona, even Korean maids like Chunxiang, the children they gave birth to cannot be regarded as Zhu Jingyuan's serious heirs.

Only children born to Daming women can be counted.

So Zhu Zhongliang treated Zhu Jingyuan's acceptance of Hu Ji as if he had added two playthings in his room, which was a waste of energy and reduced the number of normal offspring that should have been.

Zhu Jingyuan has a plan for these things:

"When I am 60 years old, Huer and Puer will both be 44 years old, and they will be at a disadvantage, just like my father.

"I don't want this to happen too many times in the future, so I plan to take two every two years, and two every time I go to a place.

"Maintain this speed, after the age of 24, before the age of 34, during this period, give birth as much as possible."

Zhu Zhongliang seemed to understand what Zhu Jingyuan meant:

"You are stuck when you are 60 years old, and your child should try to be around 30 years old, right?"

Zhu Jingyuan nodded directly:

"That's almost what it means, isn't it just right..."

Zhu Zhongliang glanced at Zhu Jingyuan up and down, and then murmured with emotion:
"I suddenly realized again, you are actually only 17 years old now..."

Zhu Jingyuan was a little unresponsive:

"I'm 17 years old, how old do you think I am..."

Zhu Zhongliang smiled and shook his head:

"Nothing...how is the plan for the submarine going?"

Zhu Jingyuan hadn't given much thought to the issue of submarines before.

In this era, submarines can be said to have just taken shape, and the typical submarine form of World War I and World War II is gradually unfolding.

But the design is still very imperfect, the hull is small, the voyage is short, the speed is slow, and the combat capability is weak.

Plus the world is, after all, the early nineteenth century, and the submarine is still considered an ungentlemanly weapon.

Most navies do not pay enough attention to submarines, and most of them have not treated submarines as serious combat ships.

Zhu Jingyuan presided over the design of various types of warships, but never mentioned the matter of submarines. No one thought it was abnormal.

In recent days, probably because he often talked about uranium mines and weapons, Zhu Zhongliang suddenly thought of submarines.

So Zhu Zhongliang began to urge Zhu Jingyuan to mention the idea of ​​submarines.

Zhu Jingyuan has been sorting out his thoughts these days, and Zhu Zhongliang also asks about the progress from time to time.

Now that Zhu Jingyuan has sorted it out, he briefly talked about the overall idea:

"My idea in terms of submarines is to temporarily abandon the study of pure submarines and develop ships with diving capabilities."

Zhu Zhongliang was obviously taken aback when he heard this:
"Isn't a submarine just a ship capable of diving? Aren't these two the same thing..."

Zhu Jingyuan explained casually:

"Obviously it is different, a pure submarine should be designed based on the needs of underwater navigation.

"This kind of submarine is suspended in the water, similar to an airship floating in the air, and its shape should also be close to that of an airship.

"The way to control floating, diving, and turning is of course similar to the wings and tail of airplanes and airships.

"This is certainly an ideal goal for submarine design, but at present it seems impractical and technically too difficult.

"The more rational choice at present, the direction that can be truly practical, is to design and build a 'boat with diving capability'.

"This kind of ship will sail on the water most of the time, and will only dive into the water when attacking or absconding.

"The design of such a submarine still has to respect the characteristics of surface ships and cannot be directly designed into a drop shape.

"When the submarine is sailing on the water surface, the propeller can still be completely submerged in the water and maintain a good sailing ability..."

The two directions mentioned by Zhu Jingyuan are actually the difference between later generations of nuclear submarines and modern submarines using air-independent propulsion systems (AIP), compared with traditional old-fashioned diesel-electric submarines.

The old-fashioned diesel-electric submarines from World War I to World War II and even before the 80s can only be regarded as diving boats.

Usually sail on the water with a diesel engine, and dive into the water when fighting, and sail with batteries.

They usually have two power systems, mainly for surface navigation and submergence.

Surface sailing is faster.

Nuclear submarines and AIP submarines are purely underwater vehicles, designed entirely for submarines, and the efficiency of surface navigation is reduced.

They usually have only one power system, which is mainly suitable for submersibles.

Submarine is faster.

Zhu Zhongliang quickly understood Zhu Jingyuan's meaning:
"The idealized pure submarine you mentioned...or the submarine that some people are currently researching, is it impossible to make it in a short time now?"

In fact, many of the earliest submarine designs look more like modern submarines at first glance.

Because the early submarine design was originally aimed at submersibles, it was relatively round on the whole.

However, due to technical reasons, due to the long-term inability to achieve continuous submersion, the design of submarines has gradually turned to ships that can dive.

Zhu Jingyuan thought for a while:

"It's not that it can't be done at all, but it's very difficult and the risk is uncontrollable to do it with the current technology.

"In order for a submarine to continue to sail underwater, it needs an engine that can continue to operate underwater.

"The engines commonly used on warships are all combustion engines, including internal combustion engines such as gasoline engines and diesel engines, and external combustion engines such as steam turbines with boilers.

"When a gas turbine is running, it needs to consume fuel and oxidant.

"Surface ships only need to store fuel, and the oxidant directly uses the oxygen in the air.

"In order for a submarine to sail directly using a gas engine, not only must it store fuel, but the key is to carry oxidizers.

"Store gaseous oxygen on the submarine, or use sodium peroxide to prepare oxygen for the crew to breathe is actually okay.

"But to supply the continuous operation of the gas turbine, that kind of storage density is far from enough.

"Only using liquid oxygen or hydrogen peroxide can barely meet the needs of long-term submersion.

"However, liquid oxygen reserves have too high requirements on the process, and hydrogen peroxide has the risk of explosion.

"The difficulty of R&D, manufacturing, and use may be higher than that of nuclear power.

"Now we can only be more conservative, use diesel engines with batteries and electric motors, and directly use nuclear power to mature.

"The diesel engine is used for surface navigation, while charging the battery, and the electric motor is used for underwater navigation.

"The energy stored in lead-acid batteries is limited, and it is impossible to sail underwater for a long time.

"It needs to be floated frequently to change the battery, or to ventilate and turn on the heat engine to charge.

"So they usually sail on the water, and they can be regarded as ships with diving capabilities."

Zhu Zhongliang understood Zhu Jingyuan's meaning, nodded slightly and subconsciously wanted to ask:
"Why specifically mention diesel engines..."

But when the words came to his lips, he reacted by himself:
"I understand that gasoline is volatile, and the submarine must be submerged and sealed, so it is very dangerous to use gasoline.

"The calorific value of gasoline is also lower than that of diesel, and the torque of diesel engine is also higher.

"So the difficulty of a well-designed submarine now is the diesel engine..."

Zhu Jingyuan immediately nodded and said:

"Yes, it is a very important technology for submarines, and it is also an important technology for the modern industrial system.

"Diesel engine technology is a technology that needs to be specially developed and researched sooner or later, and it is a hurdle that must be passed.

"The key technology of the diesel engine is the fuel injection system, solving this problem can solve most of the problems.

"I have almost written these ideas, and I will send them to the Ministry of Industry to toss in the past few days."

The diesel engine has greater torque, greater power, slower speed, and higher energy consumption ratio, which is suitable for heavy vehicles and construction machinery.

Gasoline engines have faster speed, lower torque, more stable and quiet operation, and are suitable for aircraft and light vehicles.

Historically, the development of diesel engines has been slightly slower than that of gasoline engines.

Compared with gasoline engines, diesel engines have one more threshold that must be passed-fuel injection technology.

Compared with gasoline, diesel is more stable and has no volatility. Under normal circumstances, it cannot be ignited directly with an open flame.

Diesel is more viscous than gasoline, and to allow it to burn fully in the cylinder, it needs sufficient pressure to spray and atomize.

Diesel engines require ten or even a hundred times more injection pressure than gasoline engines.

The poor performance of early diesel engines was mainly due to the early air injection system, and the fuel injection pressure could not go up all the time.

Moreover, the efficiency of this fuel injection system is very low, and even more than one-tenth of the energy of the diesel engine will be used for fuel injection.

Later, a mechanical fuel injection system was used, and with a plunger pump structure suitable for high pressure, diesel engines developed rapidly.

Now the development of diesel engines in Daming and the world is almost stuck on the threshold of fuel injection pressure.

Zhu Jingyuan didn't have the design drawing of the plunger pump in his head, but he knew its general principle and working logic.

Just draw a schematic diagram and let the craftsmen of Ming Dynasty do practical research.

Zhu Zhongliang was basically relieved when he heard what Zhu Jingyuan said with confidence:
"Then do it as soon as possible...and that nuclear power..."

Zhu Zhongliang hesitated to speak, because he had asked about atomic weapons before, and Zhu Jingyuan had already talked about the difficulty.

Making such a thing into a power pack, the difficulty of slowly releasing energy may be more difficult than directly blowing it up?

Zhu Jingyuan didn't explain in detail, so he said in a rather general way:
"I'm going as fast as I can."