Chapter 931: Staying unchanged in response to all changes

Time passed by minute by minute.

Chang Haonan frowned slightly, his eyes fixed on the computer screen.

In the huge office, the only sound left is the faint "clicking" sound caused by the occasional rotation of the mouse wheel.

Anthony Jameson's paper contains a lot of content, but it is not long. In other words, the content is a bit jumpy.

If you are a reader who has little exposure to the finite volume method, you will probably have to read it several times before you can understand its meaning.

Fortunately, although Chang Haonan is not an expert in this, he has used the COMSOL Multiphysics software a lot in his previous life, so he has some understanding of the "problem-solving ideas" of this Swedish company.

"call--"

After about half an hour, Chang Haonan finally put down the mouse in his hand, leaned back in his chair and let out a breath.

Obviously he had finished reading it.

However, his frown did not relax.

This made Wei Yongming and Song Jingming, who were not far away, a little worried.

If Mr. Chang feels that the other party is difficult to deal with after seeing this, it means that the other party must really have something.

After a few minutes, Wei Yongming, who had not dared to interrupt, finally couldn't hold it in any longer.

If you stretch your neck, you will get a knife. If you shrink your neck, you will get a knife too. Whatever the conclusion is, please don't be silent...

Therefore, after hesitating for a moment, he tentatively opened his mouth and expressed his doubts:

"Mr. Chang, I think Professor Jameson's idea is to use the spectral volume method on unstructured triangular meshes to solve the hyperbolic conservation law. However, I have conducted several calculation tests before. The spectral volume method requires a huge number of Gaussian integration points when calculating the control volume surface integral, which will increase the calculation time?"

As the head of the technical department, Wei Yongming came to see Chang Haonan today, so naturally he had read this paper in advance.

It’s just that some of the content doesn’t seem to be consistent with the other party’s product promotion.

"The paper... is just a pure theoretical process."

Chang Haonan replied:

"From theoretical derivation to specific algorithm implementation, the details in between are the key to software design."

"For example, my paper introducing the conservation level set method was also published in a journal, but others did not have the corresponding grid generation and high-order partial differential equation dimensionality reduction technology. Even if they understood the content of the paper, they could not apply it to the software."

"As for Jameson's method, it should just be a reference to the idea of ​​spectral volume method, not a direct application of spectral volume method to unstructured grids."

"Although the paper does not touch upon the subsequent application level, I speculate that they will choose to construct the discrete format using the node function values ​​of the spectral unit instead of the volume average value. In this way, the Level Set function value of the control volume boundary can be estimated by a linear combination of high-order Lagrange polynomial interpolation and second-order upwind interpolation. The total number of degrees of freedom and Gaussian integration points will also be reduced accordingly. This approach is also in line with what COMSOL is good at..."

"..."

Looking at the paper on the computer screen, Chang Haonan quickly used reverse thinking to infer the other party's specific technical route to implement the algorithm.

Wei Yongming, who was sitting on the sofa, took out a small notebook at some point and was now taking notes with his head down.

"Of course, this is just my speculation from a theoretical perspective, and it may not be 100% accurate..."

Looking at Wei Yongming who was writing furiously, Chang Haonan finally did not say anything definite and left himself a way out.

But this statement obviously had no effect.

The former's hand movements became even faster.

Song Jingming, who was standing next to him, might have received too much content that he didn't understand at all. He felt his head was a little swollen at this moment, so he took advantage of the time when Wei Yongming didn't have time to look up and quickly changed the topic from technology to management:

"Then Mr. Chang, in this situation, do we need to change the original update route?"

"For example... uh... using some newer technologies to deal with it, or something like that."

In his opinion, since Chang Haonan just showed a serious expression, it obviously showed that the other party had indeed put enough pressure on him.

This was of course not entirely Song Jingming's own idea, but the conclusion he came to after discussing it with Wei Yongming before this trip.

In the field of CFD, Torch Group actually still has some technical reserves that have not been brought out.

Mainly focused on the high-precision method level.

It’s just because of the development cycle that we can’t catch up with the original update schedule.

At present, if Torch Group wants to continue to maintain its advantages in numerical computing, especially in computational fluid dynamics, it will have to delay updates in order to introduce these more promising technologies.

However, Chang Haonan did not nod immediately.

He started preparing for the update of TORCH Multiphysics software version 2.0 more than half a year ago, which involves major improvements in three aspects: multiphase flow, topology optimization and CFD.

Now, we are only one step away from pushing the new version. If we rashly disrupt our own rhythm because of the opponent's actions, we will end up in a passive position.

In fact, when it comes down to it, it is caused by the backward means of data transmission.

As of 2001, the primary means of updating large volumes of commercial software is still through physical mailing of storage media such as CDs or hard drives.

This means that users cannot accept too high an update frequency.

This also means that malicious bugs are completely unacceptable.

Because the cycle and cost of fixing bugs are unacceptably high.

Therefore, the software testing cycle these days is generally quite long to ensure that no major problems occur.

And if the software can be upgraded online at any time like it will be more than 2.0.5 years later, then we can push a 2.1Beta version first, and then push the official version after the new technology stabilizes.

Even if there are some bugs in the first version, they can be quickly modified.

Moreover, there is an even more important point.

That paper.

Although Chang Haonan understood it and even guessed the opponent's general technical route.

But there were still some details that concerned him.

That's right, he had been frowning just now. In fact, he was not worried about the threat posed to Torch Group by friendly competitors, but was thinking about these issues.

It was just that I was misunderstood by the two people on the other side...

……

After struggling alone for a few minutes, Chang Haonan raised his head again and answered decisively:

"Update plan, no change!"

"No... unchanged?"

This decision was obviously beyond the expectations of the two people on the sofa.

"Correct."

Chang Haonan nodded, then stood up and walked to the window, looking at the city in the distance:

“On the one hand, we cannot be led by others. Even if the new version of COMSOL Multiphysics can achieve the effects they advertise in the field of CFD, we still have advantages in multiphase flow and structural topology optimization, so users will not abandon our software.”

"So the worst-case scenario is that a significant number of users start using both of our software programs for different problems, which is not completely unacceptable to us."

Having said this, he paused for a moment, then turned around and gestured in the direction of the computer screen:

"On the other hand, this paper only mentions the solution of the NS equations using the grid-centered finite volume method, but does not discuss the high computational weight problem that is common in numerically solving viscoelastic constitutive equations in practice."

"For this type of problem, the LCR method that is currently being studied more is to transform the original stress tensor evolution equation into an evolution equation in the logarithmic form of the conformation tensor matrix. This process requires repeated conversion of the stress tensor used in the calculation and the matrix logarithmic form of the conformation tensor, which can easily cause a loss of precision. If the calculation weight is too large, it may even cause the algorithm to crash."

"Of course, as a consultant for a commercial company, it is impossible to include all the technical details in the paper, but it would still be too strange not to mention them at all..."

Chang Haonan touched his chin as he spoke.

Although the sentence was clearly not finished, Wei Yongming was already a little overwhelmed:

"Boss Chang, our group has never studied the finite volume method as a key technology, right?"

"You...know it so clearly?"

"Oh, not at all."

Chang Haonan waved his hand and replied with an indifferent expression:

"When Torch Group was not officially established, I read some relevant information in order to select the technical route for the new software. I didn't expect that I could still use it now."

"Anyway... they said they'll release an update at the end of this month, so it'll only be two weeks at most. Let's just stay the same until their new version is released, and then we'll see what they're up to..."