The military-industrial scientific research system of the academic master.

Time soon came to the end of 2003.

The tracking filtering technology mentioned by Chang Haonan before has also taken shape.

Of course, it is sheer wishful thinking to produce a hardware prototype in just one week.

Even if the screwdriver produced sparks, it would be too late.

Therefore, what he actually presented was a program for simulating filtering functions.

It cannot play a practical role.

But it is enough to demonstrate the principle.

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 a simulation signal source.

"Is this the test data of the fan blade from a few days ago?"

Qu Liangsheng was sitting next to Chang Haonan. He leaned over to look at the first vibration amplitude curve and asked curiously.

"Yes."

The latter did not take his eyes off the screen, and quickly input the parameters while answering:

"The dynamic balance of the blade is better than I expected, but some parameters of the truss sandwich structure need to be further optimized to achieve a cyclic fatigue life of more than 109 cycles..."

These parameters are what need to be publicly promoted after future commercialization, so Chang Haonan doesn't mind revealing them in advance.

What's more, the other party is one of our own.

"A billion times?"

Qu Liangsheng mainly focuses on ground and offshore equipment, so he hardly needs to consider the weight of the equipment.

But even so, this cyclic fatigue life really seemed exaggerated to him.

"There's nothing we can do... The crack growth life of titanium alloy is too short, and there's almost no margin for error, so we can only raise the standards."

Chang Haonan hit the Enter key, then took a long breath, 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 400c, and the rotation speed is only in the four digits, so the conditions are relatively mild... The main difficulty lies in the balance between static strength and high-cycle fatigue performance."

Seeing that the work at hand was finished, Qu Liangsheng suddenly changed the subject:

"Speaking of which, Academician Chang, I also analyzed the imbalance compensation technology you mentioned last week after I went back..."

He pulled a notebook from his pocket and opened it.

A simple geometric model is drawn on it.

"Of course, the electromagnetic bearing-flexible rotor combination is still a long way from being implemented, so I want to use it in the improvement of existing products, including the next generation of products. I give priority to studying the contact bearing-rigid rotor combination, and then balance it by setting balancing blocks on the rotor..."

"The balancing of a rigid rotor requires two correction planes, which is equivalent to having four balancing block angles that need to be adjusted. The monotonic relationship between the optimization objective function and these four angles is not clear, so it can only be transformed into a cyclic optimization problem with four one-dimensional variables."

"Assume that the rotor correction surface is the same as the measurement surface and both are on the rotor end surface, the centrifugal force generated by the rotor unbalanced mass is mu, the maximum centrifugal force generated by the two balancing head correction masses is m, and the coordinate system rotates synchronously with the rotor, then..."

"..."

At the beginning, several graduate students nearby came over and wanted to listen to what the two big guys were discussing.

But soon someone sat back down...

In fact, if the whole issue is turned into a detailed paper, perhaps many people will be able to understand it.

But the discussion between Qu Liangsheng and Chang Haonan was so jumpy that it was really hard to follow their train of thought.

It was not until about fifteen minutes later, when even the simulation filtering results appeared on the screen, that the former finished explaining the entire derivation process.

Of the dozen people who had just surrounded him, only three were left behind Qu Liangsheng.

Judging from their wise eyes, I'm afraid they didn't really understand.

Just want to see the sequel...

While the old academician was drinking water after his speech, Chang Haonan reviewed the other party's derivation process.

It turns out that the overall idea is a coordinate rotation method.

It can be guaranteed that the stable point of the objective function is searched, and it must be the global optimal solution of the optimization problem.

Then the other party's purpose in coming to find me is already very clear...

Therefore, without Qu Liangsheng having to speak again, Chang Haonan took the initiative to ask:

"I think... Academician Qu should have tested this algorithm?"

Qu Liangsheng, who had just put down the cup, paused for a moment, then nodded:

"Yeah, but it's just a mock test like yours."

He pointed to the computer screen in front of Chang Haonan——

The result after filtering is shown above.

Even though we haven't analyzed it in detail, we can see that the noise signals other than the vibration components at the same frequency as the rotational speed are much weaker than before processing.

At least it won't steal the show.

And this result was already expected by Chang Haonan.

Therefore, he didn't even bother to look at it, 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, each other step will reduce the vibration, and the system vibration will not change suddenly. It just takes a long time and cannot meet the needs of rapid balancing, right?"

Hearing this, several graduate students who had assisted Academician Qu in the past two days stopped recording or communicating and looked in the direction of Chang Haonan.

Obviously, the latter guess was correct.

Even Qu Liangsheng did not expect that Chang Haonan could predict the result so accurately.

After opening his mouth several times, he asked with a hint of regret:

"So Academician Chang, you also think that this technology cannot be used on rigid joints?"

Although the calculation model of the contact bearing-rigid rotor is simple, the adjustment of two degrees of freedom through the slider is limited after all. Compared with the various control methods of electromagnetic bearings, its potential is indeed not good.

"Um……"

Chang Haonan looked at the notebook in front of him, organized his words a little, and then borrowed a pen from a graduate student next to him:

"Not exactly. 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 balancing head by rotating it twice, and then directly solve the algebraic equations to determine the rotation angle of the balancing block, so as to quickly find the optimal balance point... The specific strategy is probably..."

Chang Haonan quickly wrote out a matrix calculation formula on paper.

"As long as we can achieve the first round of balancing, we can save the parameter values, re-measure the remaining vibration amplitude after balancing, and enter the subsequent recursive process..."

"..."

When facing Qu Liangsheng, Chang Haonan didn't need to explain the whole process like he did in class.

As long as you explain some key points, the other party will understand.

As for more specific engineering practices, it certainly requires both parties to jointly study based on actual conditions.

So it wasn't long before he put down his pen again:

"Of course, this balancing strategy may cause a sudden increase in the amount of imbalance when identifying the initial information of the balancing head. It can only be used for rotors with a small amount of balancing correction. Specifically for centrifuges, the separation factor of a single separation stage cannot be too large..."

The graduate student next to him was quick to take the pen back at the speed of light.

It's not that he's stingy, it's just that in the past week, he's already had almost a box of ballpoint pens taken away from him by someone else for free...

Fortunately, Qu Liangsheng and Chang Haonan were focused on what was happening in front of them and did not notice this little movement.

"It's enough... not too big but enough."

The former held the notebook in front of him and read it again carefully:

"Although it is not weapon grade, it can just meet the most pressing needs of the nuclear power industry..."

In 2003, although China already had nuclear power technology and industry, they were still not very developed.

There are only three nuclear power plants in operation: Qinshan, Daya Bay and Ling'ao, which together account for 2% of the country's electricity generation.

Among them, only the Qinshan reactor was independently designed and built.

But according to the plan, the speed of nuclear power plant construction will be very fast in the next few years.

For example, the Tianwan Nuclear Power Station is currently constructing the first two VVER units.

This places higher demands on 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 would like to register your name in Jincheng?"