Chapter 27 Are you Yao Mengna’s senior?

Chang Haonan thought about the two encounters between himself and Yao Mengna, and felt that the other party seemed a little dull...

However, he was not prepared to refute the senior brother he had just met on such a trivial matter.

"Hmm... Indeed, she learns things quite quickly."

Fortunately, the topic about Yao Mengna came to an end soon.

"Junior brother, are you testing the performance of some turbine blades?" Fang Zhen looked at Chang Haonan, who was lowering his head to record data.

"No, it's just an ordinary fan blade, but it uses some aviation engine design ideas. It's a good exercise for yourself." Chang Haonan told the truth.

Although he only took this job because he wanted to make a lot of money at first, yesterday afternoon, he began to try to use the blade curved/swept design to control flow separation, and after simulating several different designs, he really got the idea. The control of flow separation within an impeller has led to some new understanding.

"Senior brother, you came so late to do an experiment?" Chang Haonan replaced a 30% throttle plate with a larger opening with a much more skillful movement than before.

"That's not true. I left a book behind when I was using the low-speed airfoil wind tunnel during the day. Come and get it." Fang Zhen said, holding up a book about the DAMP language in his hand.

"Huh?" Chang Haonan instantly caught the cover of the book and asked almost subconsciously: "You are quite efficient. Have you already started secondary development of MSC.NASTRAN?"

"Huh?" Fang Zhen felt that he had used more questioning words in the past ten minutes than in the past month: "How do you know we are doing this?"

Chang Haonan scratched his head.

"Uh... when I met Senior Sister Yao last time, she told me that you were using the CFD/CSD coupling method to do straight wing flutter analysis, but the efficiency was very low. I suggested that she try the dipole grid method. , but we need to use DAMP language for secondary development of the software, and I didn’t expect that you guys have already started doing it.”

However, Fang Zhen, who was holding a book opposite, was even more surprised than Chang Haonan: "You mean you told Yao Bo this method?"

"Yes." Chang Haonan nodded, and then told Fang Zhen the knowledge points he told Yao Mengna that day.

For a moment, the only sound left in the entire laboratory was the whirring sound of air flowing through the hairdryer.

Fang Zhen opened his mouth several times, but thousands of words were stuck in his mouth, and he didn't know what to say.

Finally, after about half a minute, Fang Zhen asked the first question with difficulty: "So you are Yao Bo's senior?"

"what?"

This time it was Chang Haonan's turn to look confused.

"It's nothing..." Fang Zhen suppressed his laughter with great difficulty: "How about this, junior brother, please join the team as soon as possible to familiarize yourself with the environment. I will go to the office tomorrow to clear a window seat for you with the best sunshine."

"Yeah, that's okay." Chang Haonan originally planned to take a few days off during the exam week and adjust his schedule, but since the other party has extended the invitation, it would be good to give him a little more time to adapt: ​​"Then I'll tell Teacher Du first and wait until the exam Tuesday. I will join the group after the main exam is over..."

"No problem, Teacher Du will definitely agree." The smile on Fang Zhen's face could hardly be concealed.

In order to prevent Chang Haonan from seeing his expression, he quickly turned his head slightly and happened to see the inconspicuous fans on the table next to him.

At this time, the experiment on the first prototype fan blade shape has been successfully completed.

Chang Haonan carefully replaced the second fan, which was the first version of the improved design.

After restarting the power, even though this is not a semi-anechoic chamber for detecting noise, the difference from the previous one can be heard with just human ears.

The noise is significantly less.

"There's something about the design of your fan." Fang Zhen leaned over and stared at the fans. Strictly speaking, they were four fans with curved blades and stared at them for a long time. "Can I pick it up?"

As a graduate student who has worked hard in the laboratory for 6 years, he knows that samples must not be touched without permission from others.

"Just be careful not to fall."

Chang Haonan is not afraid of being spotted. If Fang Zhen could analyze his design and calculation methods with just a pair of eyes, he would have become a protected object of the country long ago.

"This is...a forward-curved and forward-swept blade design?"

Fang Zhen asked with some uncertainty.

In the field of engineering design, bending and sweeping are two different definitions.

In fact, flow control is almost an eternal topic in aeroengine design, or turbine machinery design.

The idea of ​​controlling flow by changing the geometry of the cascade flow channels has been around since the 1960s and 1970s.

It's just that for a long time, it has relied more on experience and intuition, lacking sufficient theoretical tools for guidance, so it is not surprising that Fang Zhen understands this.

What Chang Haonan wants to do is to conduct a systematic study on the stacking forms of curved and swept blades on the basis of summarizing experience, so as to provide direction guidance for the design of other forms of blades in the future!

Of course, this can only be said to be the beginning.

"Well, I'm going to test the efficiency of different sweep effects on the impeller. Of course, this is just a fan, and the gas flow rate won't be very high."

Chang Haonan's hands were not idle while he was talking. He quickly changed to a new piece of graph paper and continued to draw on it.

"You..." Fang Zhen originally wanted to say that it is too early for you, an undergraduate who is doing your graduate work, to study this kind of topic. It is better to start with more practical problems first.

But he quickly recalled the talent and learning ability that Yao Mengna showed when she first joined the team two years ago.

And the undergraduate student in front of me...

Although it has not been confirmed yet, Fang Zhen basically believes that the flutter simulation idea came from Chang Haonan.

In other words, it may be more powerful than Yao Mengna...

So he finally decided to keep his mouth shut.

"I don't understand you monsters very well..." Fang Zhen shook his head and thought to himself.

"Senior brother, what did you just say?" Chang Haonan turned around and asked Fang Zhen, who was in a daze after saying only one subject.

"Ah, I want to say that you have enough time to finish your project?"

It is said that the undergraduate graduation project lasts for one academic year, but generally speaking, excluding the time when I go home during the winter vacation and the time when I first get started, it actually only lasts four or five months, and it is usually something short and quick.

"This is not my final project."

Chang Haonan's graduation project is actually completed.

"what?"

Fang Zhen became even more nervous.

Even Yao Mengna back then honestly spent more than five months in the laboratory to come up with the final result.

After all, no matter how talented you are, some operations or experience-based things still take time to hone.

When he entered the door just now, Fang Zhen saw Chang Haonan's actions in operating the equipment, which was not very skillful, so he subconsciously classified the latter as a type with rich theoretical knowledge but lack of practical experience.

But then I thought about it, it would be nice to have someone who specializes in theory and simulation, which can save a lot of energy from other people in the laboratory.

The only pity is that the current domestic foundation in this field is very weak, and there is not even much data. It may take a long time to produce results.

But it doesn’t matter, my undergraduate thesis is neither archived nor published.

Therefore, Fang Zhen has even thought about giving some of his unpublished results to Chang Haonan for use first.

By then, his affection for his senior brother will definitely increase, and then...

Then you can hand over all the simulation parts of your paper to him!

The plan goes through!

"Then I'll go back first. Junior brother, don't forget to lock the door when you finish the experiment." Fang Zhen gently put the fan back in place and left the laboratory in a good mood.

He was going to bring a huge "surprise" to Yao Mengna.