Five hundred and fiftieth IX three kinds of engines
"Look what kind of engines these are?"
Professor Claire clicked on the blackboard.
"What engine?"
Liu Lang looked at the blackboard.
"Well, this is an in-line engine, this is a V-shaped engine, and this... is a rotary engine!"
Without any thought at all, Liu Lang answered.
"Well, this question is very simple for you. Okay, then let me ask you, what are their opposition methods? What are the advantages and disadvantages? You answer it!"
This question made everyone else frown, not because the question was difficult, but because it was very difficult for Liu Lang because they felt that China's technology was still far away from the engine. Perhaps in-line engines and V-type engines were not the same.
It's not difficult. After all, these two types of engines are very common, but the rotary engine is different.
This kind of engine was not manufactured by the island country until more than ten years ago. Although its output power is very powerful, the requirements for materials are very high, and the related technology is not yet mature. Even in the United States, it is full of controversy. Even the Americans
I am still researching it myself, but Liu Lang may have just seen it, and as for the advantages and disadvantages, I am afraid he doesn’t know much about it.
However, the difficulty of this question is not too high. At least for Claire, questions of this difficulty are really rare. At least he does not ask you to write various complicated formulas.
"Okay, let me answer your question, Professor Claire. The inline engine is the most common, that is, all the cylinders are arranged side by side in a plane. Its cylinder block and crankshaft structure are simple, and it uses one cylinder head. The manufacturing cost is low and it is stable.
It has high performance, good low-speed torque characteristics, low fuel consumption, compact size, and is widely used. Its disadvantage is low power.
Adjacent cylinders are arranged at a certain angle, so that the two groups of cylinders form a plane with an angle, and the cylinders are V-shaped when viewed from the side. The height and length of the V-shaped engine are small, making it easier to arrange on the car. It
It is convenient to increase displacement and power by expanding the cylinder diameter and is suitable for higher cylinder numbers. Currently, many domestically produced mid-to-high-end models use V-type 6-cylinder engines, such as Regal, Passat and Audi A6, etc.
A simple understanding of a V-type engine is that adjacent cylinders are grouped together at a certain angle, looking like a V-shape from the side. Compared with an in-line engine, a V-type engine has a reduced height and length, which allows the engine to
The cover is lower to meet aerodynamic requirements and at the same time offset part of the vibration.
But the disadvantage is that two cylinder heads must be used, and the structure is relatively complicated. Although the height of the engine is reduced, its width is also increased accordingly, so it is not easy to install other devices in the engine compartment with a fixed space."
Liu Lang first explained these two common engines.
"Yes, the answer is completely correct, but what about the rotary engine?"
Professor Clare then asked.
"While the center of the triangular rotor revolves around the center of the output shaft, the triangular rotor itself rotates around its center. When the triangular rotor rotates, the internal ring gear centered on the center of the triangular rotor meshes with the gear centered on the center of the output shaft. The gear
It is fixed on the cylinder block and does not rotate. The triangular rotor rotates once, and the engine ignites and performs work three times.
Due to the above motion relationship, the rotation speed of the output shaft is three times the rotation speed of the rotor, which is related to the 1:1 motion relationship between the piston and the crankshaft of the reciprocating engine.
The rotary engine is small in size and therefore has low vibration. Thanks to the axial motion characteristics of the rotary engine, it can achieve high speeds without precise crankshaft balancing, and the entire engine has only two rotating parts, compared with ordinary four-stroke engines.
The structure is greatly simplified and the probability of failure is also small.
However, the intake and exhaust temperatures of the rotary engine are inconsistent, resulting in inconsistent thermal expansion and contraction on both sides of the cylinder, which eventually destroys the seal and consumes more fuel. More importantly, the rotary engine is the ancestor of the real oil-burning machine because of its
Both engine oil and fuel are poured into the cylinder through a device. In order to ensure the smooth operation of the rotor, engine oil is injected every time the fuel is injected. Naturally, the engine oil and gasoline burn together, which causes serious air pollution and consumes a lot of engine oil."
"How did you know?"
After Liu Lang finished answering, Claire asked in surprise.
"Professor Claire, although our country's industrial base is very weak, it cannot stop our yearning for the most advanced technology.
In fact, I have never seen this kind of rotary engine, nor have my teachers at Huaxia University. We only have one picture of this kind of rotary engine. Based on this picture, we analyzed many problems. As for
If you are right, please give me Professor Claire's advice!"
Liu Lang was right. He and Professor Xiong Huaizhi had never seen a real rotary engine. They only had a photo given to him by Professor Xiong's friend from an island country. This rotary engine has been used in a car from the island country.
That's all.
Professor Xiong originally built the rotary engine based on this picture. Of course, what he produced was only superficial, but with this model alone, Professor Xiong analyzed the advantages and disadvantages of this kind of engine.
In fact, he was also speculating. After all, he did not have any parameters in his hand and could only rely on his inferences about the materials and rotor motion trajectories. Liu Lang also discussed this kind of engine with Professor Xiong at that time. In Professor Xiong's view, this kind of engine
The output power is very powerful and the structure is relatively simple. It seems to be a new type of engine with great potential, but
This is because the rotation of the rotor will produce uneven impact on the inner wall of the cylinder. It may not matter for a while, but over time, especially under high temperature and high pressure conditions, the material requirements are much greater than those required by ordinary engines, and the sealing is also more demanding.
Strictly speaking, if these two points are not solved, the rotary engine will always have huge hidden dangers.
Of course, these are all Professor Xiong's speculations. He also wanted to engage in research on a rotary engine, but there was none in the country, not even a car equipped with a rotary engine. Liu Lang also inquired about it, and finally found out that the island country only has
This kind of engine can only be found in sports cars like the GTR. This kind of car is naturally not sold in China. Even if it was sold, Liu Lang couldn't afford it at that time. After all, the price exceeded 700,000 yuan, so it doesn't matter now.
At this time, Claire was surprised by Liu Lang's answer. This answer was very close to the correct answer. Has China's mechanical level reached this level? Then why did Liu Lang come to the United States to study?
"These are the things you learned in China?"
Claire finally expressed her doubts.
"Professor Claire, to be honest, in China, even the top Huaxia University and Capital University do not have any relevant information. My inference was based on the analysis of a picture by a professor named Xiong Huaizhi. This professor
I studied in Germany in the 1940s and later returned to China, where I contributed tremendously to our country’s industrial base...
I can tell you with confidence that my teacher has not been exposed to the world's advanced industrial technology since the 1970s. He cannot manufacture high-precision lathes or engines with superior performance. This is the national responsibility.
The reason is not something he can control personally.
But his ability is definitely no less than that of everyone sitting here. If he had chosen to stay abroad in the 1940s, he would have become famous and become the most famous scientist in the world. He has contributed everything he has to the development of our country.
,Such a person deserves my eternal respect!”
Liu Lang spoke his mind. Professor Xiong was a teacher worthy of everyone's respect. His ability and character were perfect in Liu Lang's eyes.