One-four-stroke star-type reciprocating engine.

What is a Four-Stroke?

The concept of the four-stroke was understood in depth when they developed the internal combustion engine.

The first step: inhale, intake stroke.

The second step: the compression stroke.

The third step: workmanship, ignition stroke.

Step 4: Exhaust stroke.

This is a four-stroke.

The four-stroke is far more powerful than the two-stroke, and the steam engine falls into the category of the two-stroke.

Four-strokes, they understand, must be in the category of the internal combustion engine.

But the star-shaped reciprocating engine, this star-shaped, made them a little blind.

The people in the class had a heated discussion for a while, and they all walked up to the podium to observe the blackboard carefully, but they couldn't help but be confused. It seems to understand, but it doesn't seem to understand.

Li Zhen asked everyone to go down, and then with chalk, he drew a line on one of the corners, writing: "Piston." ”

Put down the chalk and say, "Every 'horn' you see growing around a circle is a piston cylinder. And if I want to tell you about the star-shaped reciprocating engine, you can't avoid another concept: the cylinder block. ”

"What is a cylinder? Who's going to answer? ”

A man from the motorized courtyard stood up and said, "It's a cylinder." Load-bearing pistons, push rods, drive rods. One end is connected to the power source, and the other end is responsible for the power output, which is the cylinder block. ”

Li Zhen asked again: "Why is the previous internal combustion engine less than the power?" Now do you understand? ”

Ma Jianbin exclaimed: "I understand." I suddenly understood, Master Li, I understand this picture. Because...... Before the internal combustion engine, there was only one cylinder. If you have to plan, it's a single-cylinder engine. And the one painted by Li Shi is a multi-cylinder engine. Single-cylinder engines have only one block to provide power, and the reciprocating speed is slow and the torque is relatively small. However, in this multi-cylinder engine, multiple cylinders provide power at the same time, and the reciprocating speed will increase geometrically. ”

Li Zhenyi clapped his hands:

"Yes, that's a multi-cylinder engine. The star-type reciprocating engine is to squeeze the potential of the four-stroke engine unlimitedly. For example, let's say the horizontal bar engine revs at five revolutions per second. Then the speed of the five-cylinder engine can reach at least 25 revolutions per second. Let me tell you the most realistic question, do you think cylinders have a lifespan? ”

"Yes!"

"There must be."

"The piston is constantly moving in the cylinder, and there is wear and tear."

“……”

"A single-cylinder engine, if it has to work 400,000 revolutions a day. Then the reverse thrust proves that the cylinders of this engine wear out 400,000 times a day. If a five-cylinder engine, the same works 400,000 rpm per day. 400,000 times of wear, but it was spread out with five cylinders. Theoretically, it will also last five times longer than a horizontal bar engine. This is the most realistic question. Stability. ”

"Then, if a single-cylinder engine works at 400,000 rpm, it takes an hour. Then the five-cylinder engine works 400,000 rpm, and the time required in theory will be reduced by five times. So the rotational speed will be faster. The torque will be greater. This is the principle of a multi-cylinder engine. ”

Ma Jianbin was flushed because of the surprise, and he felt that he had opened his eyes. Master Li's head is so long.

He has studied the mobility to such an extent.

After explaining it, it feels simple, but the difficulty of starting from scratch can be imagined.

With the same power, there are only a few more cylinders, and the power is increased geometrically. Stability, safety, torque, and speed are all improved geometrically.

Ma Jianbin exclaimed: "Master Li." I already understand the principle. This concept is kind of a surprise to us. With the concept in mind, the next step is the ending technique. We'll put it on the agenda right away and start researching. ”

Li Zhen waved his hand: "You sit down first." I'm not done yet. ”

"The technical problems of multi-cylinder engines are not as complicated as you think. This issue is left for later. In addition, I will say that multi-cylinder engines are not suitable for aviation. Because it's too heavy. The body is complex and massive. If the technology is mature, it can be used to replace steam cars. ”

When they heard this, they sat up straight again and pricked up their ears to listen.

Li Zhen pointed to the picture on the blackboard: "And what I really want to say." It's a radial reciprocating engine. This is the heart of aerospace. Knowing the concept of a multi-cylinder engine, understanding a radial engine becomes simple. ”

"First of all, a few concepts, why I say that the star engine is suitable for aviation. First, it has a compact structure and occupies a small space. Second, it is lightweight. Third, the power pressing intensity is high. Fourth, strong stability, strong safety and long life. Fifth, the star engine can even achieve two-row star, three-row star, or even multi-row star. ”

"The cylinders are arranged around the rotor body. I don't need to emphasize the problem of the transmission coupling. It must be emphasized that the number of cylinders in a radial reciprocating engine must be an odd number. It can't be even. ”

Outsider Liu Jinghong wondered: "Why? ”

Ma Jianbin and others were also confused. yes, why is that?

According to this theory, the more cylinders the better, but why does it have to be an odd number? Odd and even, what does it matter to this engine?

Li Zhen said: "Because the distance is because there are multiple cylinders around the rotor and jointly provide power. Therefore, as long as it is an even number of cylinders, then there must be a top and parallel arrangement in the cylinder. Because the core of the star engine is that the multi-cylinder flat rotor workmanship, each cylinder only does a fixed angle of rotation. ”

"For example, let's say it's a five-cylinder product. Then the rotor rotates once, not five cylinders taking turns to make it rotate once. Rather, with each revolution, five cylinders are involved in the work. The first cylinder rotates the rotor one-fifth, and the second makes it two-fifths. So speculated. ”

"So, if the number of cylinders is even. Then there must be a phenomenon of counter-topping, which will cause the piston in the two cylinders to move synchronously. There will be two cylinders that will be involved in the quintile. In this way, it is bound to shake greatly. This shaking is undulating and will be fatal. ”

"So, a radial reciprocating engine has to use an odd number of cylinders. For example, five-cylinder, seven-cylinder, nine-cylinder. Double-row five-cylinder, double-row seven-cylinder. Or three rows of five cylinders, three rows of seven cylinders. ”

“……”

Everyone listened intoxicated, and the sound of inhaling cold air kept coming.

Ma Jianbin drew a sketch on paper, drew a rotor, and drew the average emissions of ten cylinders. As a result, when measured with a ruler, three or four of them were parallel. Three or four groups all produced the phenomenon of topping.

He gasped, and sure enough, everything is learned. Who would have thought that just one odd number and even number would make such a big difference.

It's just a digital concept. But the story behind it is not so simple.

Liu Jinghong, a layman, was also sweating profusely when he heard it.

That's science.

What the hell is Li Zhen's head?

If he hadn't said these problems before, then the mobile hospital would have some obsessive-compulsive disorder, and in order to pursue more power, he would have to get you an engine with more than 20 cylinders and more than 30 cylinders. As a result, it didn't really work.