Chapter 1122: We can’t expand nuclear power, but we can expand nuclear power
Time soon came to the end of 2003.
The tracking filtering technology mentioned by Chang Haonan before has begun to take shape.
Of course, it is purely a dream to come up with a hardware prototype in just one week.
Even if you hit the screwdriver with sparks, it’s too late.
Therefore, what he actually produced was actually a program that simulated the filtering function.
It does not play a practical role.
But the argument principle is still enough.
At the second seminar of the project team, Chang Haonan retrieved a data curve from the computer on the spot and input it into the program as an analog signal source.
“This is the test data of the fan blade a few days ago?”
Qu Liangsheng sat next to Chang Haonan, leaned over and looked at the first vibration amplitude curve, and asked curiously.
"That's right."
The latter did not move his eyes away from the screen, and quickly entered the parameters while replying:
"The dynamic balance of the blades It's better than I expected, but some parameters of the truss-type sandwich structure need to be further optimized to strive for a cyclic fatigue life of more than 10^9 cycles..."
These parameters are all future business The content needs to be publicized after it is transformed, so Chang Haonan doesn't mind revealing it in advance.
What's more, the other party is one of our own.
“A billion times?”
Qu Liangsheng specializes in ground and offshore equipment, so there is little need to consider the weight of the equipment.
But even so, this cyclic fatigue life really made him feel exaggerated.
“There is no way...the crack growth life of titanium alloy is too short and there is almost no fault tolerance, so we can only raise the standard.”
Chang Haonan hit the Enter key, then breathed a long sigh of relief, leaned back in his chair and waited for the calculation process to end:
"Of course, on the other hand, the maximum operating temperature of the fan blades will not exceed 400°C. , the rotation speed is only four digits, and the conditions are still relatively mild... The main difficulty lies in the balance between static strength and high cycle fatigue performance."
Seeing the end of the work at hand, Qu Liangsheng suddenly changed the topic:
"Speaking of which, Academician Chang, you mentioned the imbalance compensation technology last week. I analyzed it after I went back..."
He took out a notebook from his pocket. Open.
A simple geometric model is drawn on it.
“Of course, the electromagnetic bearing-flexible rotor combination is still too far away from being implemented, so I want to use it in the improvement of existing products, including the next generation, so I gave priority to the contact bearing-rigid rotor combination. above the body, and then balance it by setting a balance block on the rotor..."
"The balance of the rigid rotor requires two correction planes, which is equivalent to having four balance block angles that need to be adjusted. The optimization objective function and The monotonic relationship between these four angles is very unclear, so it can only be transformed into four one-dimensional variable cycle optimization problems."
"Assuming that the rotor correction surface and the measurement surface are the same and both are on the rotor end surface. The centrifugal force generated by the unbalanced mass of the rotor is mu, and the maximum centrifugal force generated by the two balance head correction mass blocks is both m. The coordinate system and the rotor rotate synchronously, then..."
"..."
< br>
At first, several graduate students nearby took the initiative to come over, wanting to hear what the two big guys were discussing.
But someone soon sat back down...
Actually, if the entire question was turned into a detailed paper, maybe many people could understand it.
But the discussion between Qu Liangsheng and Chang Haonan jumped too much, and it was really difficult to follow the train of thought.
It wasn’t until about fifteen minutes later, when even the simulated filtering results came out on the screen, that the former explained the entire derivation process.
Of the dozen or so people who had gathered around just now, only three were still behind Qu Liangsheng.
Judging from their wise eyes, they probably didn’t really understand.
I just wanted to see the follow-up...
While the old academician was drinking water after finishing his lecture, Chang Haonan went over the other party's derivation process again.
I found that the idea is generally a coordinate rotation method,
It can ensure that the stable point of the objective function is searched, and it must be the global optimal solution to the optimization problem. Then the purpose of the other party coming to find me was already obvious...
So, without Qu Liangsheng speaking again, Chang Haonan took the initiative to ask:
"I I think... Academician Qu should have already tested this algorithm?”
Qu Liangsheng, who had just put down the water glass, visibly hesitated, then nodded:
"Yeah, but it's just like yours, it's just a simulation test."
He pointed to the computer screen in front of Chang Haonan -
The filtered results were already displayed on it.
Even if there is no detailed analysis, it can be seen that the noise signal other than the vibration component of the same frequency as the rotation speed is much weaker than before processing.
At least it won’t overwhelm the guest.
And this result was already expected by Chang Haonan.
So he didn't even bother to look, but continued to discuss the issue at hand with Qu Liangsheng:
"I think the test results should be very good. Except for a few tentative steps, the rest Every step of the operation will reduce the amount of vibration, and the system vibration will not change suddenly. It just takes a long time and cannot meet the needs of quick balance, right? "
Hearing this, how many of these people? The graduate students who had worked with Academician Qu in the past two days couldn't help but stop recording or communicating, and all looked in the direction of Chang Haonan.
Obviously, the latter's guess is not wrong.
Even Qu Liangsheng didn't expect Chang Haonan to predict the result so accurately.
After opening his mouth several times in a row, he asked with a bit of regret:
"So Academician Chang, you also think that this technology cannot be used on rigid combinations?"< br>
Although the calculation model of the contact bearing-rigid rotor is simple, the adjustment range of only two degrees of freedom through the slider is limited. Compared with the various control methods of electromagnetic bearings, the potential is indeed not high. Too good.
“Well...”
Chang Haonan looked at the notebook in front of him, organized his language a little, and then borrowed a pen from a graduate student next to him:
"Not entirely, of course, the adjustment range and effect are definitely not as good as electromagnetic bearings... ”
“If we use the influence coefficient method instead, we can identify the initial information of the balance head by rotating the balance head twice, and then directly solve the algebraic equations to determine the rotation angle of the balance mass, which will make it easy to Find the optimal balance point quickly... The specific strategy is probably..."
Chang Haonan quickly listed a matrix calculation formula on the paper.
“As long as the first round of balancing can be achieved, the parameter values can be saved, and then the remaining vibration amplitude after balance can be measured again, and the subsequent recursive process can be entered..."
"..."
Facing Qu Liangsheng, Chang Haonan did not need to explain the entire process like he was in class.
As long as you explain a few key points, the other party will understand.
As for more specific engineering practice, it definitely requires joint research by both parties based on the actual situation.
So it didn’t take long for him to put down his pen again:
"Of course, this balancing strategy may cause a sudden increase in unbalance when identifying the initial information of the balancing head. It can only be used for rotors with a small balance correction amount. Specifically for centrifuges, the separation factor of a single separation stage cannot be too large... …”
The graduate student next to me had quick eyesight and quick hands, and put away the pen at the speed of light.
It’s not that he is stingy, in fact, in the past week, he has been prostituted by others for almost a box of ballpoint pens...
Fortunately, Qu Liangsheng and Chang Haonan are paying attention. In front of me, I didn't notice this small movement.
“It’s enough…not too big but enough.”
The former brought the notebook to his eyes and read it carefully again:
"Although it is not weapons-grade, it can just solve the most urgent needs of the nuclear power industry..."
This meeting in 2003 , although China already has nuclear power technology and industry, they are not very developed yet.
There are only three nuclear power plants in operation, Qinshan, Daya Bay and Ling'ao, which together account for 2% of the country's power generation.
Only Qinshan’s reactor is independently designed and built.
But according to the plan, nuclear power plants will build reactors very quickly in the next few years.
For example, the Tianwan Nuclear Power Plant is already building its first two VVER units.
This puts forward higher requirements for the supply quantity and quality of nuclear fuel.
Qu Liangsheng closed his notebook and looked at Chang Haonan solemnly:
"Academician Chang, I wonder if you are willing to go to Jincheng to make a name for yourself?"
(End of this chapter)