Equipment testing is a very serious matter, and it is certainly not a one-shot deal.

After a few repetitions, there are a series of things to do, such as data analysis and performance calibration.

After all the dust has settled in the follow-up work, it can be truly determined that the equipment has reached the pre-design indicators.

Therefore, when Chang Haonan received the news that the GPS jamming device test had been a complete success, it was already three days later.

At this time, he had returned to Shengjing by special plane from the capital, and was planning the production of turbine discs and turbine blades at the Liming Factory.

As a result, a seminar had just begun, and he was called out by the confidential secretary, saying that there was an internal phone.

Then it took about half an hour to come back.

"Mr. Chang, what are you ...... Plans changed? ”

Zhong Shihong, who was sitting on the left-hand side, leaned over and asked in a low voice.

Although he has been promoted to deputy general manager of the Liming plant, Zhong Shihong is still personally responsible for the specific production of the Taihang project.

As a senior technician business manager, he knows that his level and background in administration are not enough, and if he wants to go further, he can only continue to grasp the technical route.

By the way, I also hugged Mr. Chang's thighs.

Seeing Zhong Shihong's look of worrying that he would run away at any time, Chang Haonan smiled dumbly:

"There's no change, it's just a small project, just inform me of the results, don't worry."

The former nodded knowingly and sat back down.

It's just that I don't think much of Chang Haonan's "small project" is true.

Can the things that can be asked by the middle meeting of the president in person, can it still be a trivial matter?

It's a joke.

But in fact, Chang Haonan didn't tell a lie.

The scale of this project is not large.

There are only two core designers, him and Xu Yang, and from beginning to end, including the testing process, it only cost less than 500,000 yuan.

Although the time took a little longer, the actual work time was less than a month.

Originally, the most troublesome part should be in the GPS navigation module inside.

As a result, the Self-Defense Forces sent warmth directly, or two at once, and it took almost no effort.

In addition, because each jammer needs a complete set of military GPS positioning modules, there is basically no possibility of mass production.

For today's Chang Haonan, it is indeed a small job that is a big sesame seed.

The reason why he had to ask in person was because it involved a matter that he needed but was on his mind.

Ever since he was reborn, he has been thinking about how to solve it.

……

After a brief hiatus, the technical workshop that had just been interrupted resumed.

For this kind of scene, Chang Haonan is already familiar with the road.

It's just that this time the situation is more special.

Sitting in the conference room with him were not only the technicians of the Liming Factory who participated in the Taihang project, but also some of the engineers who were responsible for the casting of large-scale parts of the movable beams on the side of the die forging press.

After all, both parts of the work are intrinsically dependent on the same technology.

Investment precision casting.

In fact, before Chang Haonan actually entered the military system, when he was inspected at Beijing Aviation University, he proposed that numerical calculation methods could be used to quantitatively simulate and evaluate the continuous or semi-continuous casting process (Chapter 53).

For now, the formation process of castings can only be speculated based on experience and preliminary theories, and trial and error analysis are required in actual casting to determine the process plan.

The purpose of numerical simulation is to accurately obtain reasonable control parameters at all stages of casting molding, including the calculation of temperature field, flow field, stress field and concentration field. Reduce the number of tests, eliminate casting defects, and even perform tissue simulations to further control casting performance.

But that's just an idea.

If it is really implemented, as a research object in a multi-physics complex, there is a change in the state of matter, and the boundary of the research system in the whole process is still in an unstable state, it is not possible to simply copy the past experience.

Although TORCH Multiphysics is a platform with a good enough foundation, it still needs to be specially optimized for the casting process before it can be used.

"Mr. Chang, we can understand what you mean, but how to accurately express the entire filling and solidification process of investment casting in mathematical form?"

Fu Jiangwei, the chief engineer from Zhaodu Foundry Co., Ltd., took the lead in asking.

Zhaodu Casting was originally a state-owned enterprise affiliated to Zhaodu Iron and Steel Group, and later changed hands to the chief engineer of the original factory in the form of share contracting in the process of economic system transformation.

The privatization restructuring is a win-win situation, Zhaodu Iron and Steel Group was able to travel lightly and concentrate on the core business, and Zhaodu Casting gradually developed and grew after getting rid of the restrictions of the rules and regulations, and finally became the only private enterprise in the list of first-class suppliers of die forging press projects.

"It's not that hard."

Chang Haonan pulled the blackboard next to the conference room, picked up the chalk, and then turned back and asked:

"I would venture to ask, Fu Gong should have some theoretical basis in mathematics, right?"

The reason why he asked this question was not that he had any prejudices, but that all walks of life in this era were still in the stage where experience was king.

Especially in the traditional field of steel, many technicians are from the wild road and have not received systematic higher education.

If this is the case, it may be difficult to understand what Chang Haonan said next.

"Yes, I am a graduate of Jizhou Institute of Mechanical and Electrical Engineering for 80 years."

Fu Jiangwei nodded, and at the same time picked up the ballpoint pen placed next to him-

The other party asked this, obviously to show his strength.

"If you want to accurately calculate the entire investment casting process at the micro level, it is really not feasible."

"But we can think differently and divide the object of study into a continuum composed of infinitely many fluid microclusters in space, and do not study the movement and interaction of individual molecules in the casting process."

"Because macroscopic behavior within a fluid is a spatial continuum, analogue studies use macroscopic continuous mathematical methods to study fluid motion."

"For example, in the process of molten metal flowing into the cavity, the fluid model is relatively accurately described as an incompressible Newtonian fluid, so the filling process can be described by the mass equation, the momentum equation and the energy equation, and the solidification process can be approximated as a single heat conduction ......"

Chang Haonan dictated while writing the blackboard.

This part of the content may be relatively basic for some people who have done projects with him before, but there are still some barriers to understanding for others.

"All the way to this."

He said and pointed to the last equation on the blackboard:

"Up to this point, we can do it with the tools we have at hand, but the later part, that is, the prediction of the shrinkage of the keyhole in the casting, needs to be adjusted based on your experience and some experimental results."

"To determine the specific state of the shrinkage loose keyhole, my current thinking is based on the pressure loss of the dendrite in the feeding channel during the solidification process."

With that, he filled in a new list of formulas below.

"That's the parametric design and calibration here."

Chang Haonan threw the chalk head back into the chalk box, then turned the seat and faced the crowd in front of him again:

"I plan to spend two to three months to complete the model design of the entire precision casting filling and solidification process!"

(End of chapter)