Chapter 63 Stronger than Them
After the seminar, Chang Haonan was not surprised to be surrounded by a group of people again.
In addition to those who came to him to discuss fluid dynamics simulation issues, there were also some people who were very interested in the situation of MA-60.
Even Yao Mengna and Lin Shikuan who were with him were asked a lot of questions.
So it was not until about one o'clock in the morning that the three of Chang Haonan finally "escaped" from the conference room.
"Huh——"
Lin Shikuan, who had not encountered such a battle for a long time, moved his somewhat stiff body and took a deep breath with pleasure.
Although I was following Chang Haonan to get the chance, I still felt like I was surrounded and asked questions.
Cool!
But as soon as he thought about it, he felt a little worried again.
"Dr. Chang, can the flow field simulation analysis you just mentioned at the meeting really match the test flight results?"
In the past year or so, Lin Shikuan and his team In fact, engineers have been working very hard to learn from the advanced experience of foreign counterparts. Even though information is not developed and there are technical barriers in the field of engineering simulation, they have read a lot of literature and technical manuals.
You can’t really blame them for not making any outstanding achievements. After all, China has no foundation in this area.
So Lin Shikuan knows very well that even Americans who are at the forefront of aerodynamic simulations cannot guarantee the accuracy of numerical calculation results. They can only say that there are no problems with the rules.
However, Chang Haonan is ready to directly challenge the comparison between numerical calculation results and test flight data!
"Is it completely consistent? Of course I dare not say, so we need to test the flight." Chang Haonan shook his head: "But if you can choose the right simulation method, it is not difficult to control the average difference to about 5%. ”
This data shocked Lin Shikuan so much that he forgot to continue walking and just stopped in place.
In the field of engineering design, an error of 5% is an accuracy that can only be dreamed of.
You cannot find two identical leaves on a tree, nor can you find two identical air currents on the earth.
Even if the same aircraft is used for two consecutive test flights, there may be a few percent difference between the data obtained.
"But...but...how was this done?" Lin Shikuan asked in an unbelievable tone:
"We have also communicated with the French and Americans, and even they It’s impossible to do this.”
“Is it because they are hiding something?”
“This is not a technical detail, there is no need to hide it.” Chang Haonan waved his hand. >
“Besides, as long as you refer to their aircraft design cycle, you can roughly estimate that they really cannot achieve this level of accuracy.”
"But, have you ever thought about..."
At this point, Chang Haonan suddenly stopped and turned around to face Lin Shikuan behind him:
"Can they do it? Doesn't it mean that we can't do it? Or that we are stronger than them?"
"This..."
Lin Shikuan looked at it blankly. Chang Haonan with his hands in his pockets.
He could feel that what a confident spirit was hidden under the other person's calm appearance!
We are stronger than them!
How many people in the 1990s could say this from the bottom of their hearts?
However, Chang Haonan didn't just say it.
The tone and expression on his face when he said these words seemed to have a kind of magic that made others believe that he could really do it.
Yao Mengna, who had been walking alone in front, subconsciously looked back because of these words.
The other party's image seemed to grow taller at this moment.
Of course, what neither of them know is that for Chang Haonan, who returns from 2023, having this kind of thinking is really normal.
Looking at Lin Shikuan who was stunned, Chang Haonan smiled, turned around and continued walking towards the dormitory. The former finally reacted at this time and quickly caught up to Chang Haonan:
"You are right, we can be stronger than them, but in terms of aerodynamic simulation...don't say anything else. , the software we use is written by French and Americans.”
In fact, for people living in this era, it is very normal to have this kind of thinking.
Be it Yao Mengna or Lin Shikuan, their patriotism may not be any worse than that of Chang Haonan.
But feelings are one thing, reality is another.
Faced with the huge gap, one blow after another can easily make people lose hope.
But Chang Haonan can become that hope.
"Software, after all, is just a tool." He shrugged and replied: "Those who make tools are not necessarily the best at using them, just like those of us who make airplanes may not necessarily be able to fly airplanes. "
After pausing for a few seconds, he continued to add:
"But you are right. After all, other people's tools are not the most convenient. Sooner or later, we can also Use your own tools. ”
Be reasonable.
Lin Shikuan nodded after hearing this:
"Okay, I hope you are right. If you need any help during this period, just let me know. Our entire digital design team will listen to you."< br>
Of course Chang Haonan was not prepared to be polite to the other party. After all, he was still counting on gaining more management experience through these people.
“The two of us can do the flow field simulation itself. Your task is to follow the idea mentioned by Yao Bo the day before yesterday and produce the digital structure diagram of the entire aircraft as quickly as possible, so that the aircraft can be improved later. The efficiency can be greatly improved when using the wings.”
In the original timeline, the J-8F added an additional pair of wing blades to smooth out the flow field turbulence on the wing surface after carrying bombs. It seems that this is of course the method with the least impact on the overall design. Later, the Americans encountered the same problem when developing the EA18G, and the solution was to simply add a pair of wing knives.
But that doesn't mean there aren't better solutions.
A better plan means more changes. If digital design methods are not used, the delay in project progress will be very serious.
“We must do it as soon as possible.”
When Lin Shikuan said this, he hesitated.
After a few seconds, he turned around and walked back in the opposite direction.
"Eh? What are you doing?"
Yao Mengna, who was walking together, didn't react for a moment.
"Go to work overtime."
"This..."
Yao Mengna looked at Lin Shikuan who was gradually walking away, and then at Chang Haonan next to her.
"Aren't we going to go with you?"
The latter shook his head simply:
"I know the progress, and calculation and simulation rely on inspiration, so I have to have a good rest."
......
Three days later, when a J-7 aircraft borrowed by Yang Fenghao landed on the runway of Beiling Airport, Chang Haonan also changed the shape of the wing flow field. The calculation results were placed in the hands of the former.
This speed almost caught the team responsible for the project off guard - no one expected that the simulation results would be available within three days.
Actually, this is because two people spent one day converting the numerical results output by the computer into a more intuitive flow field distribution map, otherwise two days would be enough.
Yang Fenghata looked at the simulation results in front of him and took a deep breath:
“Change the schedule and test the flight in advance!”
(End of this chapter)