Chapter 440 The Dawn of Machinery Manufacturing Industry
At the same time, here at Jinghang University.
Chang Haonan’s research on high-speed rolling bearings has also entered the most critical stage.
For him, if he really just wants to design a single bearing product, whether it is for turbofan 9 or turbofan 10, it is actually not difficult.
After doing scattered things during this period, I once again saved about 300 scientific research points, which was enough to complete a mere bearing design project.
But Chang Haonan no longer has this ambition.
When you first reborn, there was no way to spend scientific research points on specific projects. After all, if you don’t have some solid and convincing results, you can’t just rely on words to persuade others to change the direction of national-level policies. ——
Even if he had full points in his verbal skills, he had no way to speak at that time.
However, that was then, and now is now. Today, Chang Haonan has the ability to influence the direction of the industry, and the perspective of looking at things is definitely different.
The reason why he wanted to bring together several top research groups on high-speed bearing research in the Science and Technology Commission system, in addition to accelerating the research progress, was naturally to prepare to promote the level of the entire industry.
And even with a tool like TORCH Multiphysics, whose computational efficiency is an order of magnitude higher than in the past, to achieve this goal, the data obtained during the research process is more important than the results.
"Mr. Chang! The first batch of experimental results have come out!"
A young man wearing blue overalls and goggles quickly walked to the row in front of him Bearing looked at the form in front of Chang Haonan.
Zhang Jing, a doctoral student in Wang Qinli’s research group.
Similar in age to Chang Haonan, if I have to say, he is even several years ahead of the latter.
When he was first asked by his mentor to work on a project in Beijing, his original intention was to refuse.
For graduate students, especially graduate students in this era, business travel is definitely a chore.
The helpless man had to lower his head under the eaves, and was finally dragged over by Wang Qinli.
However, after seeing Chang Haonan's research efficiency before and understanding the research topics they would be responsible for next, he quickly became very enthusiastic and devoted himself to the assigned work.
After this period of time, if I hadn’t still recited the ancestral precepts of respecting teachers and respecting morality, I would have forgotten Wang Qinli.
The experiment he mentioned was Chang Haonan's concentrated test of his results during this period.
"Let's go and have a look."
Chang Haonan put down the form in his hand, inserted the pen into the breast pocket of the lab coat, and strode to another room not far away.
There, a dozen pieces of equipment that were rotating at high speed were making a low roar.
Although the experiment has ended, it is obviously impossible for equipment under high-speed rotation to stop immediately from 15,000 rpm, so the bearings being tested inside still need to wait for a while before they can be taken out.
However, the impact and vibration data recorded during the entire process can still be viewed.
Chang Haonan went straight to the computer with the No. 1 logo on it.
Wang Qinli, Zhang Qinggang and other professors responsible for different research contents consciously gave him a position with the best angle.
"Mr. Chang, according to the recorded data results, the RMS amplitude of the rotor acceleration signal before maneuvering flight is 0.1190m/s^2, and the RMS amplitude during maneuvering flight is 0.1957m/s ^2, an increase of 64.45%; the RMS amplitude of the bearing contact force pulse signal before maneuvering is 19.5124N, and the RMS amplitude during maneuvering is 37.4275N, an increase of 91.81%, which is consistent with your improved mathematical model The prediction results are very close, and the comprehensive error is within 8%.”
Wang Qinli’s voice was trembling when he reported the results.
You should know that the model he improved on the Jones model before can control the dynamic performance prediction error of low-speed bearings under normal operating conditions to about 15%.
This has made Wang Qinli feel that he can leave his name in the field of mechanical processing, and even considered naming it Qinli Model.
However, it only took Chang Haonan less than half a month to raise the accuracy to a new level?
Zhang Qinggang, who was next to him, had completely forgotten that there were other people around him. He almost hugged the screen and muttered to himself:
"It's so accurate, it's so accurate..."< br>
For an engineering model, this accuracy is almost as good as a dream. However, Chang Haonan was not surprised by this. In fact, when everyone had the first meeting, the idea proposed by Wang Qinli was already quite forward-looking, and he made some modifications on it, including assembly interference, Taking into account several factors such as temperature differences and external maneuvering overloads that were previously difficult to calculate due to strong non-linearity, it is obvious that the accuracy has been greatly improved.
After looking at the data on several computers in succession, everyone’s attention has shifted to the experimental equipment not far away.
In fact, the dozen or so pieces of equipment that are decelerating next to them have been running continuously for hundreds of hours.
For the life equivalent accelerated test, these bearings have also reached the end of their life. This can be seen from the fact that the data recorded on the computer have obvious abnormalities compared with steady-state operation.
The bearings tested in each piece of equipment have specially designed typical structural parameters.
According to Chang Haonan’s calculations before the experiment, each of them will correspond to different failure modes.
The dynamic performance prediction is only a small part of the content. The final test is whether the calculation of the bearing failure mode can correspond to the actual situation.
If it can, it can directly bring China's bearing industry and even the entire machinery manufacturing industry into a new era.
An era of overtaking on a straight line!
Although this process may not be completed in three or two years.
But for Chinese researchers, difficulty has never been a problem.
The problem is that there is no hope in the past.
Better other people’s products mean more users, and more users means more and more valuable data is generated, and this data can be fed back to further optimize products.
Basically all high-end industries meet this virtuous cycle model.
In this case, if you want to achieve transcendence, you must either wait for major changes in the external environment, or simply change a track.
But Chang Haonan’s set of things completely unreasonably breaks this cycle.
Under a better algorithm framework, the amount of data I need to optimize the product may be only one-tenth of yours or even lower, so the gameplay will be different.
Soon, more than a dozen experimental equipment stopped running one after another.
After another period of cooling, the operator in charge of the experiment took out the bearings one by one.
"According to calculations, the No. 1 bearing has a maximum contact stress of 2500Mpa during operation, and the maximum shear stress of the subsurface layer is about 125μm from the surface. The failure mode is speculated to be fatigue spalling originating from the subsurface layer."
Not even You need to look at the labels on the equipment, and Chang Haonan can already repeat the calculation results of each bearing.
"Yes, the peeling area is about 50mm×15mm, the subsurface butterfly structure is about 105~129μm from the raceway surface, and the maximum length is about 40μm..."
"No. 2 bearing , the maximum dn value during operation is 2.38×106mm·r/min, and the instantaneous temperature in the contact area reaches above 300°C. The failure mode is presumed to be the fracture of the bearing ring and cage. "
"No. 3 bearing, bearing roller. The surface wear of the track and cage fails..."
"No. 4..."
"..."
"No. 16, pitting corrosion failure originated from the bearing raceway surface..."
When Chang Haonan reported the last After the failure of an experimental subject, there was no other sound in the entire laboratory except the hum generated by the operation of the computer host.
“What was the result?”
After a few seconds of silence, Chang Haonan turned around and looked at the dozens of people in front of him.
Zhang Jing held an experiment record book in his hand. At the end of each line of content, there was a check mark.
“I can match them all!”
(End of this chapter)